Pulmonary delivery in treating disorders of the central nervous system

ABSTRACT

A method for treating a disorder of the central nervous system includes administering to the respiratory tract of a patient a drug which is delivered to the pulmonary system, for instance to the alveoli or the deep lung. The drug is administered at a dose which is at least about two-fold less than the dose required by oral administration. Particles that include the drug can be employed. Preferred particles have a tap density of less than about 0.4 g/cm 3 . In addition to the medicament, the particles can include other materials such as, for example, phospholipids, amino acids, combinations thereof and others.

RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.09/877,734, filed Jun. 8, 2001, now U.S. Pat. No. 6,613,308, which is acontinuation-in-part of U.S. application Ser. No. 09/665,252, filed onSep. 19, 2000 now U.S. Pat. No. 6,514,482. The entire teachings of theabove applications are incorporated herein by reference.

BACKGROUND OF THE INVENTION

Parkinson's disease is characterized neuropathologically by degenerationof dopamine neurons in the basal ganglia and neurologically bydebilitating tremors, slowness of movement and balance problems. It isestimated that over one million people suffer from Parkinson's disease.Nearly all patients receive the dopamine precursor levodopa or L-Dopa,often in conjunction with the dopa-decarboxylase inhibitor, carbidopa.L-Dopa adequately controls symptoms of Parkinson's disease in the earlystages of the disease. However, it tends to become less effective aftera period which can vary from several months to several years in thecourse of the disease.

It is believed that the varying effects of L-Dopa in Parkinson's diseasepatients is related, at least in part, to the plasma half life of L-Dopawhich tends to be very short, in the range of 1 to 3 hours, even whenco-administered with carbidopa. In the early stages of the disease, thisfactor is mitigated by the dopamine storage capacity of the targetedstriatal neurons. L-Dopa is taken up and stored by the neurons and isreleased over time. However, as the disease progresses, dopaminergicneurons degenerate, resulting in decreased dopamine storage capacity.Accordingly, the positive effects of L-Dopa become increasingly relatedto fluctuations of plasma levels of L-Dopa. In addition, patients tendto develop problems involving gastric emptying and poor intestinaluptake of L-Dopa. Patients exhibit increasingly marked swings inParkinson's disease symptoms, ranging from a return to classicParkinson's disease symptoms, when plasma levels fall, to the so-calleddyskinesis, when plasma levels temporarily rise too high followingL-Dopa administration.

As the disease progresses, conventional L-Dopa therapy involvesincreasingly frequent, but lower dosing schedules. Many patients, forexample, receive L-Dopa every two to three hours. It is found, however,that even frequent doses of L-Dopa are inadequate in controllingParkinson's disease symptoms. In addition, they inconvenience thepatient and often result in non-compliance.

It is also found that even with as many as six to ten L-Dopa doses aday, plasma L-Dopa levels can still fall dangerously low, and thepatient can experience very severe Parkinson's disease symptoms. Whenthis happens, additional L-Dopa is administered as intervention therapyto rapidly increase brain dopamine activity. However, orallyadministered therapy is associated with an onset period of about 30 to45 minutes during which the patient suffers unnecessarily. In addition,the combined effects of the intervention therapy, with the regularlyscheduled dose can lead to overdosing, which can requirehospitalization. For example, subcutaneously administered dopaminereceptor agonist (apomorphine), often requiring a peripherally actingdopamine antagonist, for example, domperidone, to controldopamine-induced nausea, is inconvenient and invasive.

Other medical indications involving the central nervous system (CNS)require rapid delivery of a medicament such as but not limited toepilepsy, panic attacks and migraines. For example, about 2 millionpeople in the USA suffer from some form of epilepsy, with the majorityreceiving at least one of several different anti-seizure medications.The incidence of status epilepticus (the more serious form of epilepsy)is approximately 250,000. A significant number of patients also sufferfrom so-called “cluster seizures”, wherein an initial seizure forewarnsthat a series of additional seizures will occur within a relativelyshort time frame. By some reports, 75% of all patients continue toexperience seizures despite taking medication chronically. Poorcompliance with the prescribed medications is believed to be asignificant (albeit not sole) contributing factor. The importance ofcontrolling or minimizing the frequency and intensity of seizures liesin the fact that incidence of seizures has been correlated with neuronaldeficits and is believed to cause loss of neurons in the brain.

Despite chronic treatment, as many as 75% of all patients continue toexhibit periodic seizures. The uncontrolled seizures occur in manyforms. In the case of “cluster seizures,” one seizure serves notice thata cascade has begun which will lead to a series of seizures before thetotal episode passes. In certain patients, prior to the onset of asevere seizure, some subjective feeling or sign is detected by thepatient (defined as an aura). In both instances, an opportunity existsfor these patients to significantly reduce the liability of the seizurethrough “self medication”. While many patients are instructed to do so,the drugs currently available to permit effective self medication arelimited.

Panic attacks purportedly affect at least about 2.5 million people inthis country alone. The disorder is characterized by acute episodes ofanxiety, leading to difficult breathing, dizziness, heart palpitationsand fear of losing control. The disorder is believed to involve aproblem with the sympathetic nervous system (involving an exaggeratedarousal response, leading to overstimulation of adrenaline releaseand/or adrenergic neurons). Current pharmacotherapy combines selectiveserotonin re-uptake inhibitors (SSRIs), or other antidepressantmedications, with the concomitant use of benzodiazapines.

A limitation of the pharmacotherapies in current use is the delay in theonset of efficacy at the beginning of treatment. Like treatments fordepression, the onset of action of the SSRIs requires weeks rather thandays. The resulting requirement for continuous prophylactic treatmentcan, in turn, lead to significant compliance problems rendering thetreatment less effective. Therefore, there is a need for rapid onsettherapy at the beginning of treatment to manage the anticipation of thepanic attacks, as well as a treatment for aborting any attacks as soonas possible after their occurrence.

A pure vasogenic etiology/pathogenesis for migraine was first proposedin the 1930s; by the 1980s, this was replaced by a neurogenicetiology/pathogenesis, which temporarily won favor among migraineinvestigators. However, it is now generally recognized that bothvasogenic and neurogenic components are involved, interacting as apositive feedback system, with each continuously triggering the other.The major neurotransmitters implicated include serotonin (the site ofaction of the triptans), substance P (traditionally associated withmediating pain), histamine (traditionally associated with inflammation)and dopamine. The major pathology associated with migraine attacksinclude an inflammation of the dura, an increase in diameter ofmeningeal vessels and supersensitivity of the trigeminal cranial nerve,including the branches that enervate the meningeal vessels. The triptansare believed to be effective because they affect both the neural andvascular components of the migraine pathogenic cascade. Migrainesinclude Classic and Common Migraines, Cluster Headaches and TensionHeadaches.

Initial studies with sumatriptain showed that, when administeredintravenously (IV), a 90% efficacy rate was achieved. However, theefficiency rate is only approximately 60% with the oral form (versus 30%for placebo). The nasal form has proven to be highly variable, requiringtraining and skill on the part of the patient, which some of thepatients do not seem to master. The treatment also induces a bad tastein the mouth which many patients find highly objectionable. Therecurrently exists no clear evidence that any of the recent, moreselective 5HT1 receptor agonists are any more efficacious thansumatriptan (which stimulates multiple receptor subtypes; e.g., 1B, 1D,and 1F).

In addition to not providing adequate efficacy, current dosing oftriptans have at least two other deficiencies: (1) vasoconstriction ofchest and heart muscles, which produces chest tightness and pain in somesubjects; this effect also presents an unacceptable risk to hypertensiveand other CV patients, for whom the triptans are contraindicated, and(2) the duration of action of current formulations is limited, causing areturn of headache in many patients about 4 hours after initialtreatment.

Rapid onset of a hypnotic would also be quite desirable and particularlyuseful in sleep restoration therapy, as middle of night awakening anddifficulty in falling asleep again, once awakened, is common in middleaged and aging adults.

Other indications related to the CNS, such as, for example, mania,bipolar disorders, schizophrenia, appetite suppression, motion sickness,nausea and others, as known in the art, also require rapid delivery of amedicament to its site of action.

Therefore, a need exists for methods of delivery of medicaments whichare at least as effective as conventional therapies yet minimize oreliminate the above-mentioned problems.

SUMMARY OF THE INVENTION

The invention relates to methods of treating disorders of the centralnervous system (CNS). More specifically the invention relates to methodsof delivering a drug suitable in treating a disorder of the CNS to thepulmonary system and include administering to the respiratory tract of apatient in need of treatment particles comprising an effective amount ofthe medicament. In one embodiment, the patient is in need of rapid onsetof the treatment, for instance in need of rescue therapy; the medicamentis released into the patient's blood stream and reaches the medicament'ssite of action in a time interval which is sufficiently short to providethe rescue therapy or rapid treatment onset. In another embodiment, theinvention is related to providing ongoing, non-rescue therapy to apatient suffering with a disorder of the CNS.

Disorders of the nervous system include, for example, Parkinson'sdisease, epileptic and other seizures, panic attacks, sleep disorders,migraines, attention deficit hyperactivity disorders, Alzheimer'sdisease, bipolar disorders, obsessive compulsive disorders and others.

The methods of the invention are particularly useful in the ongoingtreatment and for rescue therapy in the course of Parkinson's disease.The drug or medicament employed in the methods of the invention is adopamine precursor or a dopamine agonist, for example, levodopa(L-DOPA).

In one embodiment, the invention is related to a method for treatingParkinson's disease includes administering to the respiratory tract of apatient in need of treatment or rescue therapy a drug for treatingParkinson's disease, e.g., L-Dopa. The drug is delivered to thepulmonary system, for instance to the alveoli region of the lung. Incomparison to oral administration, at least about a two fold dosereduction is employed. Doses generally are between about two times andabout ten times less than the dose required with oral administration.

In other embodiments, a method for treating a disorder of the CNSincludes administering to the respiratory tract of a patient in need oftreatment a drug for treating the disorder. The drug is administered ina dose which is at least about two times less than the dose requiredwith oral administration and is delivered to the pulmonary system.

The doses employed in the invention generally also are at least abouttwo times less than the dose required with routes of administrationother than intravenous, such as, for instance, subcutaneous injection,intramuscular injection, intra-peritoneal, buccal, rectal and nasal.

The invention further is related to methods for administering to thepulmonary system a therapeutic dose of the medicament in a small numberof steps, and preferably in a single, breath activated step. Theinvention also is related to methods of delivering a therapeutic dose ofa drug to the pulmonary system, in a small number of breaths, andpreferably in a single breath. The methods include administeringparticles from a receptacle which has a mass of particles, to asubject's respiratory tract. Preferably, the receptacle has a volume ofat least about 0.37 cm³ and can have a design suitable for use in a drypowder inhaler. Larger receptacles having a volume of at least about0.48 cm³, 0.67 cm³ or 0.95 cm³ also can be employed. The receptacle canbe held in a single dose breath activated dry powder inhaler.

In one embodiment of the invention, the particles deliver at least about10 milligrams (mg) of the drug. In other embodiments, the particlesdeliver at least about 15, 20, 25, 30 milligrams of drug. Higher amountscan also be delivered, for example the particles can deliver at leastabout 35, 40 or 50 milligrams of drug.

The invention also is related to methods for the efficient delivery ofparticles to the pulmonary system. In one embodiment, the invention isrelated to delivering to the pulmonary system particles that representat least about 70% and preferably at least about 80% of the nominalpowder dose. In another embodiment of the invention, a method ofdelivering a medicament to the pulmonary system, in a single,breath-activated step, includes administering particles, from areceptacle which has a mass of particles, to the respiratory tract of asubject, wherein at least 50% of the mass of particles is delivered.

Preferably, administration to the respiratory tract is by a dry powderinhaler or by a metered dose inhaler. The particles of the inventionalso can be employed in compositions suitable for delivery to thepulmonary system such as known in the art.

In one embodiment, particles employed in the method of the invention areparticles suitable for delivering a medicament to the pulmonary systemand in particular to the alveoli or the deep lung. In a preferredembodiment, the particles have a tap density which is less than 0.4g/cm³. In another preferred embodiment, the particles have a geometricdiameter, of at least 5 μm (microns), preferably between about 5 μm and30 μm. In yet another preferred embodiment, the particles have anaerodynamic diameter between about 1 μm and about 5 μm. In anotherembodiment, the particles have a mass median geometric diameter (MMGD)larger than 5 μm, preferably around about 10 μm or larger. In yetanother embodiment, the particles have a mass median aerodynamicdiameter (MMAD) ranging from about 1 μm to about 5 μm. In a preferredembodiment, the particles have an MMAD ranging from about 1 μm tobout 3μm.

Particles can consist of the medicament or can further include one ormore additional components. Rapid release of the medicament into theblood stream and its delivery to its site of action, for example, thecentral nervous system, is preferred. In one embodiment of theinvention, the particles include a material which enhances the releasekinetics of the medicament. Examples of suitable such materials include,but are not limited to, certain phospholipids, amino acids, carboxylatemoieties combined with salts of multivalent metals and others.

In a preferred embodiment, the energy holding the particles of the drypowder in an aggregated state is such that a patient's breath, over areasonable physiological range of inhalation flow rates is sufficient todeaggregate the powder contained in the receptacle into respirableparticles. The deaggregated particles can penetrate via the patient'sbreath into and deposit in the airways and/or deep lung with highefficiency.

The invention has many advantages. For example, pulmonary deliveryprovides on-demand treatment without the inconvenience of injections.Selective delivery of a medicament to the central nervous system can beobtained in a time frame not available with other administration routes,in particular conventional oral regimens. Thus, an effective dose can bedelivered to the site of action on the “first pass” of the medicament inthe circulatory system. By practicing the invention, relief is availableto symptomatic patients in a time frame during which conventional oraltherapies would still be traveling to the site of action. The reduceddoses employed in the methods of the invention result in a plasma druglevel which is equivalent to that obtained with the oral dose. Bloodplasma levels approaching those observed with intravenous administrationcan be obtained. Dose advantages over other routes of administration,e.g., intramuscular, subcutaneous, intra-peritoneal, buccal, rectal andnasal, also can be obtained. Furthermore, a therapeutic amount of thedrug can be delivered to the pulmonary system in one or a small numberof steps or breaths.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a plot representation of blood levels of L-Dopa in ratsfollowing administration via oral gavage or direct administration to thelungs measured by mass spectrometer.

FIG. 1B is a plot representation of blood levels of L-Dopa in ratsfollowing administration via oral gavage or direct administration to thelungs measured by HPLC.

FIG. 2A is a plot representation of blood L-Dopa levels in ratsfollowing delivery orally or directly into the lungs.

FIG. 2B is a plot representation of striatal dopamine levels in ratsfollowing delivery of L-Dopa orally or directly into the lungs.

FIG. 3 is a plot representation of blood and striatal levels of ¹⁴Cfollowing administration of ¹⁴C-L-Dopa either orally or directly to thelungs.

FIG. 4 is a plot representation of plasma ¹⁴C levels in rats following¹⁴C-L-Dopa administration via oral (gavage), tracheotomy or ventilator.

FIG. 5 is a plot representation of brain ¹⁴C levels in rats following¹⁴C-L-Dopa administration via oral (gavage), tracheotomy or ventilator.

FIG. 6A is a bar graph showing absolute ¹⁴C-Carboplatin levels inregions of the brain following intravenous (IV) and pulmonary (lung)administration.

FIG. 6B is a bar graph showing relative ¹⁴C-Carboplatin levels inregions of the brain following intravenous (IV) and pulmonary (lung)administration.

FIG. 7A is a bar graph showing absolute ¹⁴C-Carboplatin levels in animalorgans following intravenous (IV) or pulmonary (lung) administration.

FIG. 7B shows relative ¹⁴C-Carboplatin levels in animal organs followingintravenous (IV) or pulmonary (lung) administration.

FIG. 8 is a plot representation showing plasma concentration of L-Dopavs. time following oral or pulmonary administration (normalized for an 8mg dose).

FIG. 9 is a plot representation showing plasma concentration ofketoprofen vs. time for oral and pulmonary groups.

FIG. 10 is a plot representation showing plasma concentration ofketoprofen vs. time for oral group

FIG. 11 is a plasma concentration of ketoprofen vs. time for pulmonarygroup.

FIG. 12 is a plot showing RODOS curves for different powder formulationsthat include L-DOPA.

FIGS. 13A and 13B are HPLC chromatograms that depict L-DOPA recoveryfrom powders (FIG. 13A) compared to a blank sample (FIG. 13B).

FIG. 14A depicts L-DOPA plasma levels following pulmonary (lung), andoral routes.

FIG. 14B depicts L-DOPA plasma levels following pulmonary (lung), oraland intravenous administration.

FIGS. 15A and 15B show results, respectively, of oral (p.o.)andpulmonary (lung) L-DOPA on functional “placing task” in a rat model ofParkinson's disease.

FIGS. 16A and 16B show results, respectively of oral (p.o.) andpulmonary (lung) L-DOPA on functional “bracing task” in a rat model ofParkinson's disease.

FIGS. 17A and 17B show results, respectively of oral (p.o.) andpulmonary (lung) L-DOPA on functional akinesia task in a rat model ofParkinson's disease.

FIG. 18 shows results of oral (p.o.) and pulmonary (lung) delivery ofL-DOPA on functional rotation in a rat model of Parkinson's disease.

FIG. 19A depicts time to seizure onset after delivery of pulmonary andoral alprazolam 10 minutes prior to PZT administration.

FIG. 19B depicts duration of seizure after delivery of pulmonary andoral alprazolam 10 minutes prior to PZT administration.

FIG. 20A depicts time to seizure onset after delivery of pulmonary andoral alprazolam 30 minutes prior to PZT administration.

FIG. 20B depicts duration of seizure after delivery of pulmonary andoral alprazolam 30 minutes prior to PZT administration.

FIG. 21A depicts time to seizure onset for pulmonary alprazolam 10 and30 minutes prior to PZT administration.

FIG. 21B depicts duration of seizure for pulmonary alprazolam 10 and 30minutes prior to PZT administration.

DETAILED DESCRIPTION OF THE INVENTION

The features and other details of the invention, either as steps of theinvention or as combination of parts of the invention, will now be moreparticularly described and pointed out in the claims. It will beunderstood that the particular embodiments of the invention are shown byway of illustration and not as limitations of the invention. Theprinciple feature of this invention may be employed in variousembodiments without departing from the scope of the invention.

The invention is generally related to methods of treating disorders ofthe CNS. In particular, the invention is related to methods forpulmonary delivery of a drug, medicament or bioactive agent.

One preferred medical indication which can be treated by the method ofthe invention is Parkinson's disease, in particular during the latestages of the disease, when the methods described herein particularlywell suited to provide rescue therapy. As used herein, “rescue therapy”means on demand, rapid delivery of a drug to a patient to help reduce orcontrol disease symptoms. The methods of the invention also are suitablefor use in patients in acute distress observed in disorders of the CNS.In other embodiments, the methods and particles disclosed herein can beused in the ongoing (non-rescue) treatment of Parkinson's disease.

In addition to Parkinson's disease, forms of epileptical seizures suchas occurring in Myoclonic Epilepsies, including Progressive andJuvenile; Partial Epilepsies, including Complex Partial, Frontal Lobe,Motor and Sensory, Rolandic and Temporal Lobe; Benign Neonatal Epilepsy;Post-Traumatic Epilepsy; Reflex Epilepsy; Landau-Kleffner Syndrome; andSeizures, including Febrile, Status Epilepticus, and Epilepsia PartialisContinua also can be treated using the method of the invention.

Attention deficit/hyperactivity disorders (ADHD) also can be treatedusing the methods and formulations of the invention.

Sleep disorders that can benefit from the present invention includeDyssomnias, Sleep Deprivation, Circadian Rhythm Sleep Disorders,Intrinsic Sleep Disorders, including Disorders of Excessive Somnolence,Idiopathic Hypersomnolence, Kleine-Levin Syndrome, Narcolepsy, NocturnalMyoclonus Syndrome, Restless Legs Syndrome, Sleep Apnea Syndromes, SleepInitiation and Maintenance Disorders, Parasomnias, Nocturnal NyoclonusSyndrome, Nocturnal Paroxysmal Dystonia, REM Sleep Parasomnias, SleepArousal Disorders, Sleep Bruxism, and Sleep-Wake Transition Disorders.Sleep interruption often occurs around 2 to 3 a.m. and requirestreatment the effect of which lasts approximately 3 to 4 hours.

Examples of other disorders of the central nervous system which can betreated by the method of the invention include but are not limited toappetite suppression, motion sickness, panic or anxiety attackdisorders, nausea suppressions, mania, bipolar disorders, schizophreniaand others, known in the art to require rescue therapy.

Medicaments which can be delivered by the method of the inventioninclude pharmaceutical preparations such as those generally prescribedin the rescue therapy of disorders of the nervous system. In a preferredembodiment, the medicament is a dopamine precursor, dopamine agonist orany combination thereof. Preferred dopamine precursors include levodopa(L-Dopa). Other drugs generally administered in the treatment ofParkinson's disease and which may be suitable in the methods of theinvention include, for example, ethosuximide, dopamine agonists such as,but not limited to carbidopa, apomorphine, sopinirole, pramipexole,pergoline, bronaocriptine. The L-Dopa or other dopamine precursor oragonist may be any form or derivative that is biologically active in thepatient being treated.

Examples of anticonvulsants include but are not limited to diazepam,valproic acid, divalproate sodium, phenytoin, phenytoin sodium,cloanazepam, primidone, phenobarbital, phenobarbital sodium,carbamazepine, amobarbital sodium, methsuximide, metharbital,mephobarbital, mephenytoin, phensuximide, paramethadione, ethotoin,phenacemide, secobarbitol sodium, clorazepate dipotassium,trimethadione. Other anticonvulsant drugs include, for example,acetazolamide, carbamazepine, chlormethiazole, clonazepam, clorazepatedipotassium, diazepam, dimethadione, estazolam, ethosuximide,flunarizine, lorazepam, magnesium sulfate, medazepam, melatonin,mephenytoin, mephobarbital, meprobamate, nitrazepam, paraldehyde,phenobarbital, phenytoin, primidone, propofol, riluzole, thiopental,tiletamine, trimethadione, valproic acid, vigabatrin. Benzodiazepinesare preferred drugs. Examples include, but are not limited to,alprazolam, chlordiazepoxide, clorazepate dipotassium, estazolam,medazepam, midazolam, triazolam, as well as benzodiazepinones, includinganthramycin, bromazepam, clonazepam, devazepide, diazepam, flumazenil,flunitrazepam, flurazepam, lorazepam, nitrazepam, oxazepam, pirensepine,prazepam, and temazepam.

Examples of drugs for providing symptomatic relief for migraines includethe non-steroidal anti-inflammatory drugs (NSAIDs). Generally,parenteral NSAIDs are more effective against migraine than oral forms.Among the various NSAIDs, ketoprofen is considered by many to be one ofthe more effective for migraine. Its T_(max) via the oral route,however, is about 90 min. Other NSAIDs include aminopyrine, amodiaquine,ampyrone, antipyrine, apazone, aspirin, benzydamine, bromelains,bufexamac, BW-755C, clofazimine, clonixin, curcumin, dapsone,diclofenac, diflunisal, dipyrone, epirizole, etodolac, fenoprofen,flufenamic acid, flurbiprofen, glycyrrhizic acid, ibuprofen,indomethacin, ketorolac, ketorolac tromethamine, meclofenamic acid,mefenamic acid, mesalamine, naproxen, niflumic acid, oxyphenbutazone,pentosan sulfuric polyester, phenylbutazone, piroxicam, prenazone,salicylates, sodium salicylate, sulfasalazine, sulindac, suprofen, andtolmetin.

Other antimigraine agents include triptans, ergotamine tartrate,propanolol hydrochloride, isometheptene mucate, dichloralphenazone, andothers.

Agents administered in the treatment of ADHD include, among others,methylphenidate, dextroamphetamine, pemoline, imipramine, desipramine,thioridazine and carbamazepine.

Preferred drugs for sleep disorders include the benzodiazepines, forinstance, alprazolam, chlordiazepoxide, clorazepate dipotassium,estazolam, medazepam, medazolam, triazolam, as well asbenzodiazepinones, including anthramycin, bromazepam, clonazepam,devazepide, diazepam, flumazenil, flunitrazepam, flurazepam, lorasepam,nitrazepam, oxazepam, pirenzepine, prazepam, temazepam, and triazolam.Another drug is zolpidem (Ambien®, Lorex) which is currently given as a5 mg tablet with T_(max)=1.6 hours; ½ Life=2.6 hours (range between 1.4to 4.5 hours). Peak plasma levels are reached in about 2 hours with ahalf-life of about 1.5 to 5.5 hours. Still another drug is triazolam(Halcion®, Pharmacia) which is a heterocyclic benzodiazepine derivativewith a molecular weight of 343 which is soluble in alcohol but poorlysoluble in water. The usual dose by mouth is 0.125 and 0.25 mg.Temazepam may be a good candidate for sleep disorders due to a longerduration of action that is sufficient to maintain sleep throughout thenight. Zaleplon (Sonata, Wyeth Ayerst) is one drug currently approvedfor middle of night sleep restoration due to its short duration ofaction.

Other medicaments include analgesics/antipyretics for example,ketoprofen, flurbiprofen, aspirin, acetaminophen, ibuprofen, naproxensodium, buprenorphine hydrochloride, propoxyphene hydrochloride,propoxyphene napsylate, meperidine hydrochloride, hydromorphonehydrochloride, morphine sulfate, oxycodone hydrochloride, codeinephosphate, dihydrocodeine bitartrate, pentazocine hydrochloride,hydrocodone bitartrate, levorphanol tartrate, diflunisal, trolaminesalicylate, nalbuphine hydrochloride, mefenamic acid, butorphanoltartrate, choline salicylate, butalbital, phenyltoloxamine citrate,diphenhydramine citrate, methotrimeprazine, cinnamedrine hydrochloride,meprobamate, and others.

Antianxiety medicaments include, for example, lorazepam, buspironehydrochloride, prazepam, chlordizepoxide hydrochloride, oxazepam,clorazepate dipotassium, diazepam, hydroxyzine pamoate, hydroxyzinehydrochloride, alprazolam, droperidol, halazepam, chlormezanone, andothers.

Examples of antipsychotic agents include haloperidol, loxapinesuccinate, loxapine hydrochloride, thioridazine, thioridazinehydrochloride, thiothixene, fluphenazine hydrochloride, fluphenazinedecanoate, fluphenazine enanthate, trifluoperazine hydrochloride,chlorpromazine hydrochloride, perphenazine, lithium citrate,prochlorperazine, and the like.

One example of an antimonic agent is lithium carbonate while examples ofAlzheimer agents include tetra amino acridine, donapezel, and others.

Sedatives/hypnotics include barbiturates (e.g., pentobarbital,phenobarbital sodium, secobarbital sodium), benzodiazepines (e.g.,flurazepam hydrochloride, triazolam, tomazepann, midazolamhydrochloride), and others.

Hypoglycemic agents include, for example, ondansetron, granisetron,meclizine hydrochloride, nabilone, prochlorperazine, dimenhydrinate,promethazine hydrochloride, thiethylperazine, scopolamine, and others.Antimotion sickness agents include, for example, cinnorizine.

Combinations of drugs also can be employed.

In one embodiment of the invention the particles consist of amedicament, such as, for example, one of the medicaments describedabove. In another embodiment, the particles include one or moreadditional components. The amount of drug or medicament present in theseparticles can range 1.0 to about 90.0 weight percent.

For rescue therapy, particles that include one or more component(s)which promote(s) the fast release of the medicament into the bloodstream are preferred. As used herein, rapid release of the medicamentinto the blood stream refers to release kinetics that are suitable forproviding rescue therapy. In one embodiment, optimal therapeutic plasmaconcentration is achieved in less than 10 minutes. It can be achieved inas fast as about 2 minutes and even less. Optimal therapeuticconcentration often can be achieved in a time frame similar orapproaching that observed with intravenous administration. Generally,optimal therapeutic plasma concentration is achieved significantlyfaster than that possible with oral administration, for example, 2 to 10times faster.

In a preferred embodiment, the particles include one or morephospholipids, such as, for example, a phosphatidylcholine,phosphatidylethanolamine, phosphatidylglycerol, phosphatidylserine,phosphatidylinositol or a combination thereof. In one embodiment, thephospholipids are endogenous to the lung. Combinations of phospholipidscan also be employed. Specific examples of phospholipids are shown inTable 1.

TABLE 1 Dilaurylolyphosphatidylcholine (C12;0) DLPCDimyristoylphosphatidylcholine (C14;0) DMPCDipalmitoylphosphatidylcholine (C16:0) DPPCDistearoylphosphatidylcholine (18:0) DSPC Dioleoylphosphatidylcholine(C18:1) DOPC Dilaurylolylphosphatidylglycerol DLPGDimyristoylphosphatidylglycerol DMPG DipalmitoylphosphatidylglycerolDPPG Distearoylphosphatidylglycerol DSPG DioleoylphosphatidylglycerolDOPG Dimyristoyl phosphatidic acid DMPA Dimyristoyl phosphatidic acidDMPA Dipalmitoyl phosphatidic acid DPPA Dipalmitoyl phosphatidic acidDPPA Dimyristoyl phosphatidylethanolamine DMPE Dipalmitoylphosphatidylethanolamine DPPE Dimyristoyl phosphatidylserine DMPSDipalmitoyl phosphatidylserine DPPS Dipalmitoyl sphingomyelin DPSPDistearoyl sphingomyelin DSSP

The phospholipid can be present in the particles in an amount rangingfrom about 0 to about 90 weight %. Preferably, it can be present in theparticles in an amount ranging from about 10 to about 60 weight %.

The phospholipids or combinations thereof can be selected to impartcontrol release properties to the particles. Particles having controlledrelease properties and methods of modulating release of a biologicallyactive agent are described in U.S. Provisional Patent Application No.60/150,742 entitled Modulation of Release From Dry Powder Formulationsby Controlling Matrix Transition, filed on Aug. 25, 1999, U.S.Non-Provisional patent application Ser. No. 09/644,736, filed on Aug.23, 2000, with the title Modulation of Release From Dry PowderFormulations and U.S. Non-Provisional patent application Ser. No.09/792,869 filed on Feb. 23, 2001, with the title Modulation of ReleaseFrom Dry Powder Formulations. The contents of all three applications areincorporated herein by reference in their entirety. Rapid release,preferred in the delivery of a rescue therapy medicament, can beobtained for example, by including in the particles phospholipidscharacterized by low transition temperatures. In another embodiment, acombination of rapid with controlled release particles would allow arescue therapy coupled with a more sustained release in a single causeof therapy. Control release properties can be utilized in non-rescue,ongoing treatment of a disorder of the CNS.

In another embodiment of the invention the particles can include asurfactant. As used herein, the term “surfactant” refers to any agentwhich preferentially absorbs to an interface between two immisciblephases, such as the interface between water and an organic polymersolution, a water/air interface or organic solvent/air interface.Surfactants generally possess a hydrophilic moiety and a lipophilicmoiety, such that, upon absorbing to microparticles, they tend topresent moieties to the external environment that do not attractsimilarly-coated particles, thus reducing particle agglomeration.Surfactants may also promote absorption of a therapeutic or diagnosticagent and increase bioavailability of the agent.

In addition to lung surfactants, such as, for example, phospholipidsdiscussed above, suitable surfactants include but are not limited tohexadecanol; fatty alcohols such as polyethylene glycol (PEG);polyoxyethylene-9-lauryl ether; a surface active fatty acid, such aspalmitic acid or oleic acid; glycocholate; surfactin; a poloxomer; asorbitan fatty acid ester such as sorbitan trioleate (Span 85); andtyloxapol.

The surfactant can be present in the particles in an amount ranging fromabout 0 to about 90 weight %. Preferably, it can be present in theparticles in an amount ranging from about 10 to about 60 weight %.

Methods of preparing and administering particles including surfactants,and, in particular phospholipids, are disclosed in U.S. Pat. No.5,855,913, issued on Jan. 5, 1999 to Hanes et al. and in U.S. Pat. No.5,985,309, issued on Nov. 16, 1999 to Edwards et al. The teachings ofboth are incorporated herein by reference in their entirety.

In another embodiment of the invention, the particles include an aminoacid. Hydrophobic amino acids are preferred. Suitable amino acidsinclude naturally occurring and non-naturally occurring hydrophobicamino acids. Examples of amino acids which can be employed include, butare not limited to: glycine, proline, alanine, cysteine, methionine,valine, leucine, tyrosine, isoleucine, phenylalanine, tryptophan.Preferred hydrophobic amino acids, include but are not limited to,leucine, isoleucine, alanine, valine, phenylalanine, glycine andtryptophan. Amino acids include combinations of hydrophobic amino acidscan also be employed. Non-naturally occurring amino acids include, forexample, beta-amino acids. Both D, L and racemic configurations ofhydrophobic amino acids can be employed. Suitable hydrophobic aminoacids can also include amino acid analogs. As used herein, an amino acidanalog includes the D or L configuration of an amino acid having thefollowing formula: —NH—CHR—CO—, wherein R is an aliphatic group, asubstituted aliphatic group, a benzyl group, a substituted benzyl group,an aromatic group or a substituted aromatic group and wherein R does notcorrespond to the side chain of a naturally-occurring amino acid. Asused herein, aliphatic groups include straight chained, branched orcyclic C1-C8 hydrocarbons which are completely saturated, which containone or two heteroatoms such as nitrogen, oxygen or sulfur and/or whichcontain one or more units of unsaturation. Aromatic groups includecarbocyclic aromatic groups such as phenyl and naphthyl and heterocyclicaromatic groups such as imidazolyl, indolyl, thienyl, furanyl, pyridyl,pyranyl, oxazolyl, benzothienyl, benzofuranyl, quinolinyl, isoquinolinyland acridintyl.

Suitable substituents on an aliphatic, aromatic or benzyl group include—OH, halogen (—Br, —Cl, —I and —F) —O(aliphatic, substituted aliphatic,benzyl, substituted benzyl, aryl or substituted aryl group), —CN, —NO₂,—COOH, —NH₂, —NH(aliphatic group, substituted aliphatic, benzyl,substituted benzyl, aryl or substituted aryl group), —N(aliphatic group,substituted aliphatic, benzyl, substituted benzyl, aryl or substitutedaryl group)₂, —COO(aliphatic group, substituted aliphatic, benzyl,substituted benzyl, aryl or substituted aryl group), —CONH₂,—CONH(aliphatic, substituted aliphatic group, benzyl, substitutedbenzyl, aryl or substituted aryl group)), —SH, —S(aliphatic, substitutedaliphatic, benzyl, substituted benzyl, aromatic or substituted aromaticgroup) and —NH—C(═NH)—NH₂. A substituted benzylic or aromatic group canalso have an aliphatic or substituted aliphatic group as a substituent.A substituted aliphatic group can also have a benzyl, substitutedbenzyl, aryl or substituted aryl group as a substituent. A substitutedaliphatic, substituted aromatic or substituted benzyl group can have oneor more substituents. Modifying an amino acid substituent can increase,for example, the lypophilicity or hydrophobicity of natural amino acidswhich are hydrophillic.

A number of the suitable amino acids, amino acids analogs and saltsthereof can be obtained commercially. Others can be synthesized bymethods known in the art. Synthetic techniques are described, forexample, in Green and Wuts, “Protecting Groups in Organic Synthesis”,John Wiley and Sons, Chapters 5 and 7, 1991.

Hydrophobicity is generally defined with respect to the partition of anamino acid between a nonpolar solvent and water. Hydrophobic amino acidsare those acids which show a preference for the nonpolar solvent.Relative hydrophobicity of amino acids can be expressed on ahydrophobicity scale on which glycine has the value 0.5. On such ascale, amino acids which have a preference for water have values below0.5 and those that have a preference for nonpolar solvents have a valueabove 0.5. As used herein, the term hydrophobic amino acid refers to anamino acid that, on the hydrophobicity scale has a value greater orequal to 0.5, in other words, has a tendency to partition in thenonpolar acid which is at least equal to that of glycine.

Combinations of hydrophobic amino acids can also be employed.Furthermore, combinations of hydrophobic and hydrophilic (preferentiallypartitioning in water) amino acids, where the overall combination ishydrophobic, can also be employed. Combinations of one or more aminoacids and one or more phospholipids or surfactants can also be employed.Materials which impart fast release kinetics to the medicament arepreferred.

The amino acid can be present in the particles of the invention in anamount of at least 10 weight %. Preferably, the amino acid can bepresent in the particles in an amount ranging from about 20 to about 80weight %. The salt of a hydrophobic amino acid can be present in theparticles of the invention in an amount of at least 10% weight.Preferably, the amino acid salt is present in the particles in an amountranging from about 20 to about 80 weight %. Methods of forming anddelivering particles which include an amino acid are described in U.S.patent application Ser. No. 09/382,959, filed on Aug. 25, 1999, entitledUse of Simple Amino Acids to Form Porous Particles During Spray Dryingand in U.S. Non-Provisional patent application Ser. No. 09/644,320,filed on Aug. 23, 2000, titled Use of Simple Amino Acids to Form PorousParticles, the teachings of both are incorporated herein by reference intheir entirety.

In another embodiment of the invention, the particles include acarboxylate moiety and a multivalent metal salt. One or morephospholipids also can be included. Such compositions are described inU.S. Provisional Application No. 60/150,662, filed on Aug. 25, 1999,entitled Formulation for Spray-Drying Large Porous Particles, and U.S.Non-Provisional patent application Ser. No. 09/644,105, filed on Aug.23, 2000, titled Formulation for Spray-Drying Large Porous Particles,the teachings of both are incorporated herein by reference in theirentirety. In a preferred embodiment, the particles include sodiumcitrate and calcium chloride.

Other materials, preferably materials which promote fast releasekinetics of the medicament can also be employed. For example,biocompatible, and preferably biodegradable polymers can be employed.Particles including such polymeric materials are described in U.S. Pat.No. 5,874,064, issued on Feb. 23, 1999 to Edwards et al., the teachingsof which are incorporated herein by reference in their entirety.

The particles can also include a material such as, for example, dextran,polysaccharides, lactose, trehalose, cyclodextrins, proteins, peptides,polypeptides, fatty acids, inorganic compounds, phosphates.

In one specific example, the particles include (by weight percent) 50%L-Dopa, 25% DPPC, 15% sodium citrate and 10% calcium chloride. Inanother specific example, the particles include (by weight percent) 50%L-Dopa, 40% leucine and 10% sucrose. In yet another embodiment theparticles include (by weight percent) 10% benzodiazepine, 20% sodiumcitrate, 10% calcium chloride and 60% DPPC.

In a preferred embodiment, the particles of the invention have a tapdensity less than about 0.4 g/cm³. Particles which have a tap density ofless than about 0.4 g/cm³ are referred herein as “aerodynamically lightparticles”. More preferred are particles having a tap density less thanabout 0.1 g/cm³. Tap density can be measured by using instruments knownto those skilled in the art such as but not limited to the Dual PlatformMicroprocessor Controlled Tap Density Tester (Vankel, N.C.) or a GeoPyc™instrument (Micrometrics Instrument Corp., Norcross, Ga. 30093). Tapdensity is a standard measure of the envelope mass density. Tap densitycan be determined using the method of USP Bulk Density and TappedDensity, United States Pharmacopeia convention, Rockville, Md., 10thSupplement, 4950-4951, 1999. Features which can contribute to low tapdensity include irregular surface texture and porous structure.

The envelope mass density of an isotropic particle is defined as themass of the particle divided by the minimum sphere envelope volumewithin which it can be enclosed. In one embodiment of the invention, theparticles have an envelope mass density of less than about 0.4 g/cm³.

Aerodynamically light particles have a preferred size, e.g., a volumemedian geometric diameter (VMGD) of at least about 5 microns (μm). Inone embodiment, the VMGD is from about 5 μm to about 30 μm. In anotherembodiment of the invention, the particles have a VMGD ranging fromabout 10 μm to about 30 Lm. In other embodiments, the particles have amedian diameter, mass median diameter (MMD), a mass median envelopediameter (MMED) or a mass median geometric diameter (MMGD) of at least 5μm, for example from about 5 μm and about 30 μm.

The diameter of the spray-dried particles, for example, the VMGD, can bemeasured using an electrical zone sensing instrument such as aMultisizer IIe, (Coulter Electronic, Luton, Beds, England), or a laserdiffraction instrument (for example Helos, manufactured by Sympatec,Princeton, N.J.). Other instruments for measuring particle diameter arewell know in the art. The diameter of particles in a sample will rangedepending upon factors such as particle composition and methods ofsynthesis. The distribution of size of particles in a sample can beselected to permit optimal deposition to targeted sites within therespiratory tract.

Aerodynamically light particles preferably have “mass median aerodynamicdiameter” (MMAD), also referred to herein as “aerodynamic diameter”,between about 1 μm and about 5 μm. In another embodiment of theinvention, the MMAD is between about 1 μm and about 3 μm. In a furtherembodiment, the MMAD is between about 3 μm and about 5 μm.

Experimentally, aerodynamic diameter can be determined by employing agravitational settling method, whereby the time for an ensemble ofparticles to settle a certain distance is used to infer directly theaerodynamic diameter of the particles. An indirect method for measuringthe mass median aerodynamic diameter (MMAD) is the multi-stage liquidimpinger (MSLI).

The aerodynamic diameter, d_(aer), can be calculated from the equation:d _(aer) =d _(g)√ρ_(tap)where d_(g) is the geometric diameter, for example the MMGD, and ρ isthe powder density.

Particles which have a tap density less than about 0.4 g/cm³, mediandiameters of at least about 5 μm, and an aerodynamic diameter of betweenabout 1 μm and about 5 μm, preferably between about 1 μm and about 3 μm,are more capable of escaping inertial and gravitational deposition inthe oropharyngeal region, and are targeted to the airways, particularlythe deep lung. The use of larger, more porous particles is advantageoussince they are able to aerosolize more efficiently than smaller, denseraerosol particles such as those currently used for inhalation therapies.

In comparison to smaller, relatively denser particles the largeraerodynamically light particles, preferably having a median diameter ofat least about 5 μm, also can potentially more successfully avoidphagocytic engulfment by alveolar macrophages and clearance from thelungs, due to size exclusion of the particles from the phagocytes'cytosolic space. Phagocytosis of particles by alveolar macrophagesdiminishes precipitously as particle diameter increases beyond about 3μm. Kawaguchi, H., et al., Biomaterials 7: 61-66 (1986); Krenis, L. J.and Strauss, B., Proc. Soc. Exp. Med., 107: 748-750 (1961); and Rudt, S.and Muller, R. H., J Contr. Rel., 22: 263-272 (1992). For particles ofstatistically isotropic shape, such as spheres with rough surfaces, theparticle envelope volume is approximately equivalent to the volume ofcytosolic space required within a macrophage for complete particlephagocytosis.

The particles may be fabricated with the appropriate material, surfaceroughness, diameter and tap density for localized delivery to selectedregions of the respiratory tract such as the deep lung or upper orcentral airways. For example, higher density or larger particles may beused for upper airway delivery, or a mixture of varying sized particlesin a sample, provided with the same or different therapeutic agent maybe administered to target different regions of the lung in oneadministration. Particles having an aerodynamic diameter ranging fromabout 3 to about 5 μm are preferred for delivery to the central andupper airways. Particles having and aerodynamic diameter ranging fromabout 1 to about 3 μm are preferred for delivery to the deep lung.

Inertial impaction and gravitational settling of aerosols arepredominant deposition mechanisms in the airways and acini of the lungsduring normal breathing conditions. Edwards, D. A., J Aerosol Sci., 26:293-317 (1995). The importance of both deposition mechanisms increasesin proportion to the mass of aerosols and not to particle (or envelope)volume. Since the site of aerosol deposition in the lungs is determinedby the mass of the aerosol (at least for particles of mean aerodynamicdiameter greater than approximately 1 μm), diminishing the tap densityby increasing particle surface irregularities and particle porositypermits the delivery of larger particle envelope volumes into the lungs,all other physical parameters being equal.

The low tap density particles have a small aerodynamic diameter incomparison to the actual envelope sphere diameter. The aerodynamicdiameter, d_(aer), is related to the envelope sphere diameter, d (Gonda,I., “Physico-chemical principles in aerosol delivery,” in Topics inPharmaceutical Sciences 1991 (eds. D. J. A. Crommelin and K. K. Midha),pp. 95-117, Stuttgart: Medpharm Scientific Publishers, 1992)), by theformula:d _(aer) −d√ρwhere the envelope mass ρ is in units of g/cm³. Maximal deposition ofmonodispersed aerosol particles in the alveolar region of the human lung(˜60%) occurs for an aerodynamic diameter of approximately d_(aer)=3 μm.Heyder, J. et al., J Aerosol Sci., 17: 811-825 (1986). Due to theirsmall envelope mass density, the actual diameter d of aerodynamicallylight particles comprising a monodisperse inhaled powder that willexhibit maximum deep-lung deposition is:d=3/√ρμm (where ρ<1 g/cm³);where d is always greater than 3 μm. For example, aerodynamically lightparticles that display an envelope mass density, ρ=0.1 g/cm³, willexhibit a maximum deposition for particles having envelope diameters aslarge as 9.5 μm. The increased particle size diminishes interparticleadhesion forces. Visser, J., Powder Technology, 58: 1-10. Thus, largeparticle size increases efficiency of aerosolization to the deep lungfor particles of low envelope mass density, in addition to contributingto lower phagocytic losses.

The aerodynamic diameter can be calculated to provide for maximumdeposition within the lungs. Previously this was achieved by the use ofvery small particles of less than about five microns in diameter,preferably between about one and about three microns, which are thensubject to phagocytosis. Selection of particles which have a largerdiameter, but which are sufficiently light (hence the characterization“aerodynamically light”), results in an equivalent delivery to thelungs, but the larger size particles are not phagocytosed. Improveddelivery can be obtained by using particles with a rough or unevensurface relative to those with a smooth surface.

In another embodiment of the invention, the particles have an envelopemass density, also referred to herein as “mass density” of less thanabout 0.4 g/cm³. Particles also having a mean diameter of between about5 μm and about 30 μm are preferred. Mass density and the relationshipbetween mass density, mean diameter and aerodynamic diameter arediscussed in U.S. application Ser. No. 08/655,570, filed on May 24,1996, which is incorporated herein by reference in its entirety. In apreferred embodiment, the aerodynamic diameter of particles having amass density less than about 0.4 g/cm³ and a mean diameter of betweenabout 5 μm and about 30 μm mass mean aerodynamic diameter is betweenabout 1 μm and about 5 μm.

Suitable particles can be fabricated or separated, for example byfiltration or centrifugation, to provide a particle sample with apreselected size distribution. For example, greater than about 30%, 50%,70%, or 80% of the particles in a sample can have a diameter within aselected range of at least about 5 μm. The selected range within which acertain percentage of the particles must fall may be for example,between about 5 and about 30 μm, or optimally between about 5 and about15 μm. In one preferred embodiment, at least a portion of the particleshave a diameter between about 9 and about 11 μm. Optionally, theparticle sample also can be fabricated wherein at least about 90%, oroptionally about 95% or about 99%, have a diameter within the selectedrange. The presence of the higher proportion of the aerodynamicallylight, larger diameter particles in the particle sample enhances thedelivery of therapeutic or diagnostic agents incorporated therein to thedeep lung. Large diameter particles generally mean particles having amedian geometric diameter of at least about 5 μm.

In a preferred embodiment, suitable particles which can be employed inthe method of the invention are fabricated by spray drying. In oneembodiment, the method includes forming a mixture including L-Dopa oranother medicament, or a combination thereof, and a surfactant, such as,for example, the surfactants described above. In a preferred embodiment,the mixture includes a phospholipid, such as, for example thephospholipids described above. The mixture employed in spray drying caninclude an organic or aqueous-organic solvent.

Suitable organic solvents that can be employed include but are notlimited to alcohols for example, ethanol, methanol, propanol,isopropanol, butanols, and others. Other organic solvents include butare not limited to perfluorocarbons, dichloromethane, chloroform, ether,ethyl acetate, methyl tert-butyl ether and others.

Co-solvents include an aqueous solvent and an organic solvent, such as,but not limited to, the organic solvents as described above. Aqueoussolvents include water and buffered solutions. In one embodiment, anethanol water solvent is preferred with the ethanol:water ratio rangingfrom about 50:50 to about 90:10 ethanol:water.

The spray drying mixture can have a neutral, acidic or alkaline pH.Optionally, a pH buffer can be added to the solvent or co-solvent or tothe formed mixture. Preferably, the pH can range from about 3 to about10.

Suitable spray-drying techniques are described, for example, by K.Masters in “Spray Drying Handbook”, John Wiley & Sons, New York, 1984.Generally, during spray-drying, heat from a hot gas such as heated airor nitrogen is used to evaporate the solvent from droplets formed byatomizing a continuous liquid feed. Other spray-drying techniques arewell known to those skilled in the art. In a preferred embodiment, arotary atomizer is employed. An example of suitable spray driers usingrotary atomization includes the Mobile Minor spray drier, manufacturedby Niro, Denmark. The hot gas can be, for example, air, nitrogen orargon.

In a specific example, 250 milligrams (mg) of L-Dopa in 700 milliliters(ml) of ethanol are combined with 300 ml of water containing 500 mgL-Dopa, 150 mg sodium citrate and 100 mg calcium chloride and theresulting mixture is spray dried. In another example, 700 ml of watercontaining 500 mg L-Dopa, 100 sucrose and 400 mg leucine are combinedwith 300 ml of ethanol and the resulting mixture is spray dried.

The particles can be fabricated with a rough surface texture to reduceparticle agglomeration and improve flowability of the powder. Thespray-dried particles have improved aerosolization properties. Thespray-dried particle can be fabricated with features which enhanceaerosolization via dry powder inhaler devices, and lead to lowerdeposition in the mouth, throat and inhaler device.

The particles of the invention can be employed in compositions suitablefor drug delivery to the pulmonary system. For example, suchcompositions can include the particles and a pharmaceutically acceptablecarrier for administration to a patient, preferably for administrationvia inhalation. The particles may be administered alone or in anyappropriate pharmaceutically acceptable carrier, such as a liquid, forexample saline, or a powder, for administration to the respiratorysystem. They can be co-delivered with larger carrier particles, notincluding a therapeutic agent, the latter possessing mass mediandiameters for example in the range between about 50 μm and about 100 μm.

Aerosol dosage, formulations and delivery systems may be selected for aparticular therapeutic application, as described, for example, in Gonda,I. “Aerosols for delivery of therapeutic and diagnostic agents to therespiratory tract,” in Critical Reviews in Therapeutic Drug CarrierSystems, 6: 273-313, 1990; and in Moren, “Aerosol dosage forms andformulations,” in: Aerosols in Medicine. Principles, Diagnosis andTherapy, Moren, et al., Eds, Esevier, Amsterdam, 1985.

The method of the invention includes delivering to the pulmonary systeman effective amount of a medicament such as, for example, a medicamentdescribed above. As used herein, the term “effective amount” means theamount needed to achieve the desired effect or efficacy. The actualeffective amounts of drug can vary according to the specific drug orcombination thereof being utilized, the particular compositionformulated, the mode of administration, and the age, weight, conditionof the patient, and severity of the episode being treated. In rescuetherapy, the effective amount refers to the amount needed to achieveabatement of symptoms or cessation of the episode. In the case of adopamine precursor, agonist or combination thereof it is an amount whichreduces the Parkinson's symptoms which require rescue therapy. Dosagesfor a particular patient are described herein and can be determined byone of ordinary skill in the art using conventional considerations,(e.g. by means of an appropriate, conventional pharmacologicalprotocol). For example, effective amounts of oral L-Dopa range fromabout 50 milligrams (mg) to about 500 mg. In many instances, a commonongoing (oral) L-Dopa treatment schedule is 100 mg eight (8) times aday. During rescue therapy, effective doses of oral L-Dopa generally aresimilar to those administered in the ongoing treatment.

For being effective during rescue therapy, plasma levels of L-dopagenerally are similar to those targeted during ongoing (non-rescuetherapy) L-Dopa treatment. Effective amounts of L-Dopa generally resultin plasma blood concentrations that range from about 0.5 microgram(μg)/liter(1) to about 2.0 μg/l.

It has been discovered in this invention that pulmonary delivery ofL-Dopa doses, when normalized for body weight, result in at least a2-fold increase in plasma level as well as in therapeutical advantagesin comparison with oral administration. Significantly higher plasmalevels and therapeutic advantages are possible in comparison with oraladministration. In one example, pulmonary delivery of L-Dopa results ina plasma level increase ranging from about 2-fold to about 10-fold whencompared to oral administration. Plasma levels that approach or aresimilar to those obtained with intravenous administration can beobtained. Similar findings were made with other drugs suitable intreating disorders of the CNS, such as, for example, ketoprofen.

Assuming that bioavailability remains the same as dosage is increased,the amount of oral drug, e.g. L-Dopa, ketoprofen, required to achieveplasma levels comparable to those resulting from pulmonary delivery bythe methods of the invention can be determined at a given point afteradministration. In a specific example, the plasma levels 2 minutes afteroral and administration by the methods of the invention, respectively,are 1 μg/ml L-Dopa and 5 μg/ml L-Dopa. Thus 5 times the oral dose wouldbe needed to achieve the 5 μg/ml level obtained by administering thedrug using the methods of the invention. In another example, the L-Dopaplasma levels at 120 minutes after administration are twice as high withthe methods of the invention when compared to oral administration. Thustwice as much L-Dopa is required after administration 1 μg/ml followingoral administration in comparison to the amount administered using themethods of the invention.

To obtain a given drug plasma concentration, at a given time afteradministration, less drug is required when the drug is delivered by themethods of the invention than when it is administered orally. Generally,at least a two-fold dose reduction can be employed in the methods of theinvention in comparison to the dose used in conventional oraladministration. A much higher dose reduction is possible. In oneembodiment of the invention, a five fold reduction in dose is employedand reductions as high as about ten fold can be used in comparison tothe oral dose.

At least a two-fold dose reduction also is employed in comparison toother routes of administration, other than intravenous, such as, forexample, intramuscular, subcutaneous, buccal, nasal, intra-peritoneal,rectal.

In addition or alternatively to the pharmacokinetic effect, (e.g., serumlevel, dose advantage) described above, the dose advantage resultingfrom the pulmonary delivery of a drug, e.g., L-Dopa, used to treatdisorders of the CNS, also can be described in terms of apharmacodynamic response. Compared to the oral route, the methods of theinvention avoid inconsistent medicament uptake by intestines, avoidanceof delayed uptake following eating, avoidance of first pass catabolismof the drug in the circulation and rapid delivery from lung to brain viaaortic artery.

As discussed above, rapid delivery to the medicament's site of actionoften is desired. Preferably, the effective amount is delivered on the“first pass” of the blood to the site of action. The “first pass” is thefirst time the blood carries the drug to and within the target organfrom the point at which the drug passes from the lung to the vascularsystem. Generally, the medicament is released in the blood stream anddelivered to its site of action within a time period which issufficiently short to provide rescue therapy to the patient beingtreated. In many cases, the medicament can reach the central nervoussystem in less than about 10 minutes, often as quickly as two minutesand even faster.

Preferably, the patient's symptoms abate within minutes and generally nolater than one hour. In one embodiment of the invention, the releasekinetics of the medicament are substantially similar to the drug'skinetics achieved via the intravenous route. In another embodiment ofthe invention, the T_(max) of the medicament in the blood stream rangesfrom about 1 to about 10 minutes. As used herein, the term T_(max) meansthe point at which levels reach a maximum concentration. In many cases,the onset of treatment obtained by using the methods of the invention isat least two times faster than onset of treatment obtained with oraldelivery. Significantly faster treatment onset can be obtained. In oneexample, treatment onset is from about 2 to about 10 times faster thanthat observed with oral administration.

If desired, particles which have fast release kinetics, suitable inrescue therapy, can be combined with particles having sustained release,suitable in treating the chronic aspects of a condition. For example, inthe case of Parkinson's disease, particles designed to provide rescuetherapy can be co-administered with particles having controlled releaseproperties.

The administration of more than one dopamine precursor, agonist orcombination thereof, in particular L-Dopa, carbidopa, apomorphine, andother drugs can be provided, either simultaneously or sequentially intime. Carbidopa, for example, is often administered to ensure thatperipheral carboxylase activity is completely shut down. Intramuscular,subcutaneous, oral and other administration routes can be employed. Inone embodiment, these other agents are delivered to the pulmonarysystem. These compounds or compositions can be administered before,after or at the same time. In a preferred embodiment, particles that areadministered to the respiratory tract include both L-Dopa and carbidopa.The term “co-administration” is used herein to mean that the specificdopamine precursor, agonist or combination thereof and/or othercompositions are administered at times to treat the episodes, as well asthe underlying conditions described herein.

In one embodiment regular chronic (non-rescue) L-Dopa therapy includespulmonary delivery of L-Dopa combined with oral carbidopa. In anotherembodiment, pulmonary delivery of L-Dopa is provided during the episode,while chronic treatment can employ conventional oral administration ofL-Dopa/carbidopa.

Preferably, particles administered to the respiratory tract travelthrough the upper airways (oropharynx and larynx), the lower airwayswhich include the trachea followed by bifurcations into the bronchi andbronchioli and through the terminal bronchioli which in turn divide intorespiratory bronchioli leading then to the ultimate respiratory zone,the alveoli or the deep lung. In a preferred embodiment of theinvention, most of the mass of particles deposits in the deep lung oralveoli.

Administration of particles to the respiratory system can be by meanssuch as known in the art. For example, particles are delivered from aninhalation device. In a preferred embodiment, particles are administeredvia a dry powder inhaler (DPI). Metered-dose-inhalers (MDI), nebulizersor instillation techniques also can be employed.

Various suitable devices and methods of inhalation which can be used toadminister particles to a patient's respiratory tract are known in theart. For example, suitable inhalers are described in U.S. Pat. No.4,069,819, issued Aug. 5, 1976 to Valentini, et al., U.S. Pat. No.4,995,385 issued Feb. 26, 1991 to Valentini, et al., and U.S. Pat. No.5,997,848 issued Dec. 7, 1999 to Patton, et al. Other examples include,but are not limited to, the Spinhaler®) (Fisons, Loughborough, U.K.),Rotahaler® (Glaxo-Wellcome, Research Triangle Technology Park, NorthCarolina), FlowCaps® (Hovione, Loures, Portugal), Inhalator®(Boehringer-Ingelheim, Germany), and the Aerolizerg (Novartis,Switzerland), the diskhaler (Glaxo-Wellcome, RTP, NC) and others, suchas known to those skilled in the art. In one embodiment, the inhaleremployed is described in U.S. patent application No. 09/835,302,entitled Inhalation Device and Method, by David A. Edwards, et al.,filed on Apr. 16, 2001. The entire contents of this application areincorporated by reference herein.

The invention further is related to methods for administering to thepulmonary system a therapeutic dose of the medicament in a small numberof steps, and preferably in a single, breath activated step. Theinvention also is related to methods of delivering a therapeutic dose ofa drug to the pulmonary system, in a small number of breaths, andpreferably in one or two single breaths. The methods includesadministering particles from a receptacle having, holding, containing,storing or enclosing a mass of particles, to a subject's respiratorytract.

In one embodiment of the invention, delivery to the pulmonary system ofparticles is by the methods described in U.S. patent application, HighEfficient Delivery of a Large Therapeutic Mass Aerosol, application Ser.No. 09/591,307, filed Jun. 9, 2000, and those described in theContinuation-in-Part of U.S. application Ser. No. 09/591,307, which isfiled concurrently herewith. The entire contents of both theseapplications are incorporated herein by reference. As disclosed therein,particles are held, contained, stored or enclosed in a receptacle.Preferably, the receptacle, e.g. capsule or blister, has a volume of atleast about 0.37 cm³ and can have a design suitable for use in a drypowder inhaler. Larger receptacles having a volume of at least about0.48 cm³, 0.67 cm³ or 0.95 cm³ also can be employed.

In one example, at least 50% of the mass of the particles stored in theinhaler receptacle is delivered to a subject's respiratory system in asingle, breath-activated step. In another embodiment, at least 10milligrams of the medicament is delivered by administering, in a singlebreath, to a subject's respiratory tract particles enclosed in thereceptacle. Amounts as high as 15, 20, 25, 30, 35, 40 and 50 milligramscan be delivered.

In one embodiment, delivery to the pulmonary system of particles in asingle, breath-actuated step is enhanced by employing particles whichare dispersed at relatively low energies, such as, for example, atenergies typically supplied by a subject's inhalation. Such energies arereferred to herein as “low.” As used herein, “low energy administration”refers to administration wherein the energy applied to disperse and/orinhale the particles is in the range typically supplied by a subjectduring inhaling.

The invention also is related to methods for efficiently deliveringpowder particles to the pulmonary system. In one embodiment of theinvention, at least about 70% and preferably at least about 80% of thenominal powder dose is actually delivered. As used herein, the term“nominal powder dose” is the total amount of powder held in areceptacle, such as employed in an inhalation device. As used herein,the term nominal drug dose is the total amount of medicament containedin the nominal amount of powder. The nominal powder dose is related tothe nominal drug dose by the load percent of drug in the powder.

In a specific example, dry powder from a dry powder inhaler receptacle,e.g., capsule, holding 25 mg nominal powder dose having at 50% L-Dopaload, i.e., 12.5 mg L-Dopa, is administered in a single breath. Based ona conservative 4-fold dose advantage, the 12.5 mg delivered in onebreath are the equivalent of about 50 mg of L-Dopa required in oraladministration. Several such capsules can be employed to deliver higherdoses of L-Dopa. For instance a size 4 capsule can be used to deliver 50mg of I-Dopa to the pulmonary system to replace (considering the sameconservative 4-fold dose advantage) a 200 mg oral dose.

Properties of the particles enable delivery to patients with highlycompromised lungs where other particles prove ineffective for thoselacking the capacity to strongly inhale, such as young patients, oldpatients, infirm patients, or patients with asthma or other breathingdifficulties. Further, patients suffering from a combination of ailmentsmay simply lack the ability to sufficiently inhale. Thus, using themethods and particles for the invention, even a weak inhalation issufficient to deliver the desired dose. This is particularly importantwhen using the particles of the instant invention as rescue therapy fora patient suffering from debilitating illness of the central nervoussystem for example but not limited to migraine, anxiety, psychosis,depression, bipolar disorder, obsessive compulsive disorder (OCD),convulsions, seizures, epilepsy, Alzheimer's, and especially,Parkinson's disease.

The present invention will be further understood by reference to thefollowing non-limiting examples.

EXEMPLIFICATIONS Example 1

In vivo tests were performed to compare oral and tracheal administrationof L-Dopa in a rat model. Animals received an IP injection of theperipheral decarboxylase inhibitor carbidopa (Sigma, St. Louis, Mo.)(200 mg/kg) one hour prior to administration of L-Dopa. Under ketamineanesthesia, the animals were divided into two groups. In the first groupof animals (N=4), L-Dopa (8 mg) was suspended in saline containing 2%methylcellulose and given via oral gavage. In the second group (N=5) asmall tracheotomy was performed to permit placement of a pipette tipwith a modified 2 mm opening through the trachea and into the lungs. Thepipette tip was pre-loaded with powdered L-Dopa (8 mg) and wasinterfaced with an oxygen tank using silicone tubing. Coinciding withthe respiratory cycle of the animal, L-Dopa was pushed into the lungsusing a burst of oxygen (5 liters/minute). Blood samples (200 μl) werewithdrawn from a previously placed femoral cannula at the following timepoints: 0 (immediately prior to L-Dopa administration), 1, 5, 15, 30, 45and 60 minutes following L-Dopa administration.

Blood levels of L-Dopa, measured, respectively, by mass spectrometry orHPLC, following administration via oral gavage or direct administrationinto the lungs are shown in FIGS. 1A and 1B. The increase in bloodlevels of L-Dopa over time following oral administration was modest. Incontrast, administration into the lungs produced a robust and rapid risein L-Dopa levels which peaked between 1 and 5 minutes post drugadministration. L-Dopa levels in this group decreased between 5 and 15minutes and remained stable thereafter. Data are presented as themean±SEM ng L-Dopa level/ml blood.

Relationship between blood L-Dopa levels and striatal dopamine levelsfollowing delivery of L-Dopa either orally or directly into the lungs,as described above, are shown in FIGS. 2A and 2B. FIG. 2A shows bloodL-Dopa levels immediately prior to L-Dopa (baseline) and at 2, 15 and 45minutes following L-Dopa (N=4-6 per time point for each group). Onceagain, the levels following administration into the lungs show a robustand rapid increase in L-Dopa levels, relative to the modest increasesfollowing oral administration.

FIG. 2B shows dopamine levels in the striatum from the same animalsshown in FIG. 2A. Immediately following withdrawal of the blood sample,the brains were removed and striatum dissected free. Tissue levels ofdopamine were determined using high performance liquid chromatography(HPLC). Note that the marked difference in blood L-Dopa levels seenbetween the two treatments at two minutes was followed, later in time,by more modest but significant differences in striatal levels ofdopamine. Blood levels are presented as the mean±SEM ng L-Dopa levels/mlblood. Striatal levels of dopamine are presented as the mean±SEM ngdopamine/mg protein.

Blood and striatal levels of ¹⁴C following administration of ¹⁴C-L-Dopaas generally described above were also determined and are shown in FIG.3. A total of 25 μCi of radiolabeled L-Dopa was mixed with unlabelledL-Dopa to provide a total drug concentration of 8 mg/rat. Blood sampleswere taken at 2, 5 and 15 minutes post drug administration L-Dopa (N=6per time point for each group). At 5 or 15 minutes post L-Dopa, thestriatum was removed and both the blood and tissues samples were assayedfor ¹⁴C levels using scintillation. The zero minute plasma values arededuced from other many studies using radioactive agents.

Once again, a robust and rapid increase in plasma levels was achievedvia the pulmonary route, which was reflected in increased dopamineactivity in the brain at both the 5 minute and 15 minute time points(relative to oral administration).

Direct comparison of plasma ¹⁴C following administration of ¹⁴C-L-Dopavia oral gavage, inhalation using a tracheotomy (as described above) orventilator (Harvard Apparatus, Inc., Holliston, Mass.) is shown in FIG.4. Corresponding brain ¹⁴C-L-Dopa levels are shown in FIG. 5. Allanimals were briefly anesthetized using 1% Isoflurane and immobilized ina harness to allow blood removal via a previously placed femoralcannula. Blood samples were removed at 0, 2, 5, and 15 minutes postadministration. For L-Dopa administration using the ventilator, a 24gauge catheter was placed within the trachea and the L-Dopa (25 μCi) wasadministered over a 3-5 second period using a tidal volume of 1 ml and100 strokes/minutes. Striatal tissue samples were processed fordeterminations of levels of radioactivity using scintillation counts.Both the plasma and brain levels of ¹⁴C were comparably elevated usingboth the conventional tracheotomy methods and the ventilator.

Example 2

Blood, brain and peripheral organ levels of ¹⁴C were determinedfollowing administration of ¹⁴C—Carboplatin via either IV or pulmonaryadministration. A total of 100 μCi of radiolabeled carboplatin was mixedwith unlabelled carboplatin to provide a total drug concentration of 8mg/rat. All animals were anesthetized using ketamine. For IVadministration, carboplatin was administered via a previously placedfemoral cannula. For pulmonary administration, a 24 gauge catheter wasplaced within the trachea and the carboplatin was administered using aHarvard ventilator over a 3-5 second period using a tidal volume of 1 mland 100 strokes/minutes. Blood samples were taken at 10 minutes postdrug administration (N=6 per time point for each group). Brains wereremoved and dissected into various regions including the olfactory,frontal, and occipital cortices, the hippocampus, striatum, andcerebellum. Peripheral organs included the kidneys, spleen, heart,testes, and muscle. All samples were then processed for determinationsof ¹⁴C levels using scintillation.

Results are shown in Table 2, which shows scintillation counts of¹⁴C-levels in plasma, brain and peripheral organs following¹⁴C-carboplatin (100 μCi/8 mg) administration, and in FIGS. 6A-6B and7A-7B. Absolute plasma levels of ¹⁴C were higher following IVadministration. However, the absolute brain levels were comparablesuggesting that delivery to the brain at this time point was relativelyselective. This point is clearer when the ratio of brain to blood ¹⁴Clevels was calculated. Following pulmonary delivery, ¹⁴C levels were2833% higher than observed following IV administration. Absolute levelsof ¹⁴C in peripheral tissue was also lower following pulmonaryadministration (92% lower relative to IV). In contrast to the largedifferences in selectivity seen in the brain, the relative peripheralselectivity (derived from dividing the levels of radioactivity inperipheral organs by that in the blood) was only 47% higher in thepulmonary group. Interestingly though, the highest levels of ¹⁴C inperipheral tissue were found in the heart. Together, these data suggestthat the brain and the heart may represent sites of preferentialdelivery at time point immediately following pulmonary drugadministration.

TABLE 2 10 Minutes Plasma Levels IV 994.348 Lung (n = 6) (% Difference)102.215 −89.72% (n = 6) Absolute Brain Levels IV 29.47 (nCi/gram) Lung27.29 Relative Brain IV 0.03 Selectivity Lung 0.88 (Brain/Blood) (%Difference) +2833% IV(Br/Bl)/Lung(Br/Bl) Absolute Tissue IV 0.03 LevelsLung 0.88 (Peripheral Organs) (% Difference) +2833% *excludes kidneyIV(Br/Bl)/Lung(Br/Bl) Relative Peripheral IV 0.44 Selectivity Lung 0.65(Peripheral/Blood) (% Difference) +47.727% *excludes kidneyIV(Per/Bl)/Lung(Per/Bl)

Example 3

Particles comprising L-Dopa and suitable for inhalation were produced asfollows. 2.00123 g DPPC (Avanti Polar Lipids, Lot #G160PC-25) was addedto 2.80 L of ethanol and stirred to dissolve. 0.0817 g L-Dopa (Spectrum,Lot 0Q0128, Laguna Hills, Calif.), 0.9135 g Sodium Citrate (Dehydrate)(Spectrum Lot NX0195), and 0.5283 g Calcium Chloride (Dehydrate)(Spectrum Lot NT0183) were added to 1.2 L of water and dissolved. Thesolutions were combined by adding the water solution to the ethanolsolution and then the solutions were allowed to stir until the solutionwas clear. The weight percent of the formulation was approximately: 20%L-Dopa, 50% DPPC, 20% Sodium Citrate, 10% Calcium Chloride.

The final solution was then spray dried in a Niro dryer (Niro, Inc.,Columbus, MD) using a rotary atomizer and nitrogen drying gas followingthe direction of the manufacturer, using the following spray conditions:T_(inlet)=120° C., T_(outlet)=54° C., feed rate=65 ml/min, heatnitrogen=38 mm H₂O, atomizer speed=20,000 rpm (V24 atomizer used).

The resulting particle characteristics were: Mass Median AerodynamicDiameter (MMAD)=2.141 μm and Volume Median Geometric Diameter(VMGD)=10.51 μm.

Under ketamine anesthesia, six rats received pulmonary administration ofthe formulation described above (20/50/20/10 L-Dopa/DPPC/SodiumCitrate/Calcium Chloride).

The results are shown in FIG. 8. This Fig. shows blood levels of L-Dopafollowing administration via oral gavage or direct administration intothe lungs via insufflation. L-Dopa levels were measured using both HPLC.Animals received an IP injection of the peripheral decarboxylaseinhibitor carbi-dopa (200 mg/kg) 1 hour prior to administration ofL-Dopa. Under ketamine anesthesia, the animals were divided into 2groups. In the first group, animals were fasted overnight and L-Dopa (8mg) was suspended in saline containing 1% methylcellulose and given viaoral gavage. In the second group, insufflation was used to deliver theL-Dopa formulation directly into the lungs. Blood samples (200 μl) werewithdrawn from a previously placed femoral cannula at the following timepoints: 0 (immediately prior to L-Dopa administration), 2, 5, 15, and 30minutes following L-Dopa administration. The increase in blood levels ofL-Dopa over time following oral administration was modest. In contrast,administration into the lungs produced a robust and rapid rise in L-Dopalevels. L-Dopa levels in this group remained elevated relative to oraldelivery at 30 minutes post drug administration. Data were normalized toa dose of 8 mg/kg (the total oral gavage dose). Data are presented asthe mean (±SEM) ng L-Dopa/ml blood.

Example 4

Ketoprofen/DPPC/maltodextrin particles were prepared and administered invivo.

Ketoprofen (99.5%) was obtained from Sigma, (St. Louis, Mo.),dipalmitoyl phosphatidyl choline (DPPC) from Avanti Polar Lipids,(Alabaster, Ala.) and maltodextrin, M100 (Grain Processing Corp.,Muscatine, Iowa).

To prepare ketoprofen/DPPC/Maltodextrin solutions, maltodextrin (0.598g) was added to 0.60 L USP water. DPPC (0.901 g) was added to 1.40 Lethanol and stirred until dissolved. The water and ethanol solutionswere combined, resulting in a cloudy solution. 500 ml of this stocksolution was used for each run. The addition of ketoprofen to theDPPC/Maltodextrin stock solution is described in Table 3.

A Niro Atomizer Portable Spray Dryer (Niro, Inc., Columbus, Md.) wasused to produce the dry powders. Compressed air with variable pressure(1 to 5 bar) ran a rotary atomizer (2,000 to 30,000 rpm) located abovethe dryer. Liquid feed of the ketoprofen/DPPC/Maltodextrin solutions,with varying rate (20 to 66 ml/min), was pumped continuously by anelectronic metering pump (LMI, model #A151-192s) to the atomizer. Boththe inlet and outlet temperatures were measured. The inlet temperaturewas controlled manually; it could be varied between 100° C. and 400° C.,with a limit of control of 5° C. The outlet temperature was determinedby the inlet temperature and such factors as the gas and liquid feedrates; it varied between 50° C. and 130° C. A container was tightlyattached to the 6″ cyclone for collecting the powder product. Thespraying conditions for each solution is given in Table 4, which showsthat the spraying conditions were held nearly constant throughout thestudy. The total recovery and yield for each solution is given in Table5.

The particles were characterized using the Aerosizer (TSI, Inc.,Amherst, Mass.) and the RODOS dry powder disperser (Sympatec Inc.,Princeton, N.J.) as instructed by the manufacturer. For the RODOS, thegeometric diameter was measured at 2 bars. The material from run #5 wasalso characterized using a gravimetric collapsed Andersen CascadeImpactor (ACI, 2 stage, Anderson Inst., Sunyra, Ga.). The samples wereexamined using a scanning electron microscope (SEM).

Table 5 indicates that increasing the weight % of ketoprofen led to adecrease in yield. The addition of ketoprofen to the stock solutionlinearly decreased yield. This may be due to a decrease in meltingtemperature for DPPC when mixed with ketoprofen, leading to the yieldloss.

Table 6 shows that the particles ranged in diameter from 8.8 μm to 10.2μm (VMGD) and from 2.65 μm to 3.11 μm (MMAD). The lowest MMAD particleswere for the 8.4% loading material (run #5).

Table 7 shows the results of a Andersen Collapsed Impactor study (ACI,gravimetric, n=2) of the material from run #5, the 8.4% loadingmaterial. The fine particle fractions (FPF) below 5.6 μm and below 3.4μm are consistent with powders expected to be respirable.

TABLE 3 Sample ID Ketoprofen added (mg) Total solids (g/L) % KetoprofenRun #1 0 1.000 0 Run #2 8.0 1.016 1.6 Run #3 15.1 1.030 3.0 Run #4 30.11.060 5.7 Run #5 46.0 1.092 8.4 Run #6 63.0 1.126 11.2

TABLE 4 Temperature Liquid Gas Rotor Inlet Sample (° C.) Feed PressureSpeed Dew- ID Inlet Outlet (ml/min) (mmH₂O) (RPM) point (° C.) Run #1115 36 75 40 18,600 −27.0 Run #2 113 38 85 40 18,400 −26.8 Run #3 110 3885 39 18,300 −26.4 Run #4 110 39 85 38 18,400 −25.9 Run #5 110 38 86 3918,400 −25.4 Run #6 110 38 85 38 18,400 −25.0

TABLE 5 Sample Weight Collected Theoretical Yield Actual Yield ID (mg)(mg) (% Theoretical) Run #1 186 500 37.2 Run #2 195 508 38.4 Run #3 147515 28.5 Run #4 127 530 24.0 Run #5  89 546 16.3 Run #6  67 563 11.9

TABLE 6 Sample ID MMAD (μm) Std Dev MGVD (μm, 2 bar) Run #1 3.11 1.489.0 Run #2 3.01 1.37 9.3 Run #3 2.83 1.40 10.3 Run #4 2.84 1.41 10.4 Run#5 2.65 1.39 9.8 Run #6 2.83 1.38 8.8

TABLE 7 Stage 0 1.33 mg Stage 2 2.75 mg Stage F 3.17 mg Capsule Fill12.37 mg  Weight < 5.6 μm 5.92 FPF_(5.6)  0.479 Weight < 3.4 μm 3.17FPF_(3.4)  0.256350 mg of particles containing 8% ketoprofen in 60/40 DPPC/maltodextrinwere produced as described above and administered to 20 Sprague Dawleyrats. Each of 8 rats were given 7 mg of powder via insufflation, andeach of 7 rats were orally given 7 mg of powder dissolved in 50%ethanol. Time points were set at 0, 5, 15, 30, 60, 120, 240, 360 and 480minutes. For t=0, 4 animals were tested without dosing. For each timepoint after, samples were taken from either 3 or 4 rats. Each rat wasused for 4 time points, with 3 or 4 animals each in four groups. Theanimals were distributed as follows: 3 animals oral at 5, 30, 120, 360minutes; 4 animals insufflation at 15, 60, 240, 480 minutes. Sufficientblood was drawn at each time point for the ketoprofen plasma assay.Blood samples were centrifuged, the plasma collected and then frozen at−20° C. prior to shipment to the contract laboratory for analysis. Theassay used in this study has a lower detection limit of 1.0 mg/ml.

Rats were dosed with ketoprofen via either oral or pulmonaryadministration to determine if the pulmonary route would alter the timerequired to achieve maximum plasma concentration. The results (FIGS.9-11) show that the pulmonary delivery route leads to a very rapiduptake with C_(max) occurring at ≦10 minutes. The rats that receivedoral doses of ketoprofen displayed somewhat anomalous pharmacokineticbehavior, with the relative bioavailability being about half of thatdisplayed for rats dosed via the pulmonary route. This result wasunexpected as ketoprofen is 90% orally bioavailable in the human model.This anomaly for the orally dosed rats does not, however, invalidate thesignificance of the early C_(max) seen for the rats dosed via thepulmonary route.

The results are provided in Table 8. The averages were calculated alongwith the standard errors and p values. The results are also presentedgraphically in FIGS. 9-11, wherein FIG. 9 shows both data sets, FIG. 10gives the oral dosing results and FIG. 11 shows the insufflationresults. For FIG. 9, points with p<0.05 are marked with “*” and pointswith p<0.01 are marked with “**”. For FIGS. 10 and 11, AUC (area underthe curve) was performed via numerical integration of the curve withsmooth interpolation.

At t=0, all rats showed ketoprofen levels below the detection limit forthe assay. From t=5 min to t=60 min, the insufflated rats hadsignificantly higher plasma levels of ketoprofen. At t=120 min and t=240min, the plasma levels of ketoprofen of the two groups werestatistically equivalent. At t=360 min and t=480, the plasma levels ofketoprofen for both groups approached the detection limit for the assay.

The ratio of the AUCs for insulflated rats vs. orally dosed was about 2.The plasma concentrations for ketoprofen at the early time points werestatistically significant as well.

C_(max) for the insufflated rats clearly occurred at <15 min and C_(max)for the orally dosed rats occurred between 15-60 min. Due to the largestandard error and the relatively low plasma levels for this group, itis not possible to accurately determine the time required for C_(max).

Pulmonary administration resulted in C_(max) occurring very quickly (<15min) compared to oral dosing (t=15 to 60 min).

The insufflated rats showed higher bioavailability compared to theorally dosed rats. This is unexpected as previous studies have shownketoprofen to have consistently high (>90%) bioavailability in humanswhen dosed orally, subcutaneously or rectally. Since the pharmokineticbehavior of ketoprofen delivered orally is well-known, the anomalousresults seen here for the orally dosed group do not invalidate theresults seen for the insufflation group.

TABLE 8 Oral Dosing Dosing Group Pulmonary Group Time Avg. St. Avg. Std.P Min. (ug/ml) Dev. (ug/ml) Dev. Value  0 1.0 N/A 1.0 N/A  5 1.7 0.759.6 1.27 0.0003  15 2.1 0.76 7.6 0.28 0.0000  30 1.9 0.12 5.5 0.760.0012  60 2.0 0.13 4.5 0.60 0.0002 120 1.7 0.31 2.4 0.44 0.0929 240 1.40.05 1.8 0.63 0.2554 360 1.0 0.06 1.8 0.35 0.0224 480 1.0 0.00 1.3 0.470.2174 Average plasma levels of Ketoprofen from oral and pulmonary group

Example 5

The following experimental methods and instrumentation were employed todetermine the physical characteristics of particles including L-DOPA andsuitable for pulmonary delivery.

Aerodynamic diameter was analyzed using the API AeroDisperser andAerosizer (TSI, Inc., St. Paul, Minn.) following standard procedures(Alkermes SOP# MS-034-005). Sample powder was introduced and dispersedin the AeroDisperser and then accelerated through a nozzle in theAerosizer. A direct time-of-flight measurement was made for eachparticle in the Aerosizer, which was dependent on the particle'sinertia. The time-of-flight distribution was then translated into amass-based aerodynamic particle size distribution using a force balancebased on Stokes law.

Geometric diameter was determined using a laser diffraction technique(Alkermes SOP# MS-021-005). The equipment consists of a HELOSdiffractometer and a RODOS disperser (Sympatec, Inc., Princeton, N.J.).The RODOS disperser applies a shear force to a sample of particles,controlled by the regulator pressure of the incoming compressed air. Thedispersed particles travel through a laser beam where the resultingdiffracted light pattern produced is collected by a series of detectors.The ensemble diffraction pattern is then translated into a volume-basedparticle size distribution using the Fraunhofer diffraction model, onthe basis that smaller particles diffract light at larger angles.

The aerodynamic properties of the powders dispersed from the inhalerdevice were assessed with a 2-stage MkII Anderson Cascade Impactor(Anderson Instruments, Inc., Smyrna, Ga.). The instrument consists oftwo stages that separate aerosol particles based on aerodynamicdiameter. At each stage, the aerosol stream passes through a set ofnozzles and impinges on the corresponding impaction plate. Particleshaving small enough inertia will continue with the aerosol stream to thenext stage, while the remaining particles will impact upon the plate. Ateach successive stage, the aerosol passes through nozzles at a highervelocity and aerodynamically smaller particles are collected on theplate. After the aerosol passes through the final stage, a filtercollects the smallest particles that remain.

Prior to determining the loading of drug within a dry powder, the drughad to be first be separated from the excipients within the powder. Anextraction technique to separate L-Dopa from the excipient DPPC wasdeveloped. Particles were first dissolved in 50% chloroform/50%methanol. The insoluble L-Dopa was pelleted out and washed with the samesolvent system and then solubilized in 0.5 M hydrochloric acid. DPPC wasspiked with L-DOPA to determine recovery. Samples were injected onto areverse phase high pressure liquid chromatography (HPLC) for analysis.

Separation was achieved using a Waters Symmetry C18 5-μm column(150-mm×4.6-mm ID). The column was kept at 30° C. and samples were keptat 25° C. Injection volume was 10 μL. The mobile phase was prepared from2.5% methanol and 97.5% aqueous solution (10.5 g/L citric acid, 20 mg/LEDTA, 20 mg/L 1-octanesulfonic acid sodium salt monohydrate). Mobilephase was continually stirred on a stir plate and degassed through aWaters in-line degassing system. L-Dopa was eluted under isocraticconditions. Detection was performed using an ultraviolet detector set atwavelength 254 nm.

Since the average single oral dose of L-Dopa generally ranges from100-150 mg, experiments were conducted to prepare particles suitable forinhalation which included high loads of L-Dopa. Formulations of 20% and40% L-Dopa load were studied. Carbidopa, a decarboxylase inhibitor givenin conjunction with L-Dopa to prevent peripheral decarboxylation, wasalso included at a 4:1 weight/weight (w/w) ratio in some of theformulations. L-Dopa and combination of L-Dopa and carbidopa weresuccessfully sprayed with DPPC formulations. The optimal formulationconsisted of L-Dopa and/or carbidopa, 20% (w/w) sodium citrate, and 10%(w/w) calcium chloride, and the remainder dipalmitoyl phosphatidylchloline (DPPC).

Details on formulations and the physical properties of the particlesobtained are summarized in Table 9. The aerodynamic size or the massmedian aerodynamic diameter (MMAD) was measured with an Aerosizer, andthe geometric size or the volume median geometric diameter (VMGD) wasdetermined by laser diffraction, and the fine particle fraction (FPF)was measured using a 2-stage Andersen Cascade Impactor. As shown in FIG.12 and by the VMGD ratios in Table 9, the powders were flow rateindependent. Scanning electron micrography was employed to observe theparticles.

TABLE 9 VMGD Load (%) Yield VMGD (μm) at ratio MMAD FPF (%) ID (%) 2 bar0.5/4.0 bar (μm) 5.6/3.4 L- Dopa/Carbi dopa 20/0 >40 9.9 NA 2.7 NA40/0 >40 8.0 1.2 3.3 42/17 20/5  42 10 1.6 3.1 64/38 40/10 >20 7.4 1.63.8 40/14

L-Dopa integrity appeared to be preserved through the formulation andspray drying process. L-Dopa was extracted from L-Dopa powders andanalyzed by reverse phase HPLC. No impurities were detected in theL-Dopa powders (FIG. 13A); the early peaks eluted around 1-2 minutes aredue to solvent as can be seen from FIG. 13B which is a blank sample thatdid not contain L-Dopa. The purity of L-Dopa recovered from theparticles was 99.8% and 99.9% respectively for the 20% and 40% loadedparticles.

To determine the loading (weight percent) of L-Dopa within the powder,the L-Dopa was first separated from the excipients in the formulationand then analyzed by reverse phase HPLC. Results of the L-Dopa recoveryfrom the powders and the final load calculations are given in Table 10.Both extraction recoveries and load determination were satisfactory. Thedetermined actual weight percent of L-Dopa in the powder wasapproximately 87% of the theoretical drug load.

TABLE 10 Powder Formulation Extraction recovery % Actual load (%) 20/0100 ± 4.5 17.3 ± 0.2 40/0 101 ± 2.8 35.0 ± 5.4

Example 6

Determinations of plasma levels of L-Dopa were made following IVinjection, oral gavage, or insufflation into the lungs. Carbidopagenerally is administered to ensure that peripheral decarboxylaseactivity is completely shut down. In this example, animals received anintraperitoneal (IP) injection of the peripheral decarboxylase inhibitorcarbidopa (200 mg/kg) 1 hour prior to administration of L-Dopa. Underketamine anesthesia, the animals were divided into 3 groups. In thefirst group of animals, L-Dopa (2 mg) was suspended in saline containing1% methylcellulose and 1% ascorbic acid and given via oral gavage. Inthe second group, an insufflation technique was used for pulmonaryadministration of particles including L-Dopa (20% loading density). Alaryngoscope was used to visualize the rat's epiglottis and theblunt-tip insufflation device (PennCentury Insufflation powder deliverydevice) was inserted into the airway. A bolus of air (3 cc), from anattached syringe, was used to delivery the pre-loaded powder from thechamber of the device into the animal's lungs. A total of 10 mg ofpowder (2 mg L-Dopa) was delivered. In the third group, apreviously-placed femoral cannula was used to delivery a bolus (2-3second) of L-Dopa (2 mg). Blood samples (200 μL) were withdrawn fromeach animal using the femoral cannula at the following timepoints: 0(immediately prior to L-Dopa administration), 2, 5, 15, 30, 60, 120, and240 minutes following L-Dopa administration. All samples were processedfor L-Dopa determinations using HPLC.

The results of a pharmacokinetic study using the procedure described areshown in FIGS. 14A and 14B. The results of a comparison of pulmonarydelivery of L-Dopa with oral administration are depicted in FIG. 14A.Following insufflation, peak plasma levels of L-Dopa were seen at theearliest time point measured (2 minutes) and began to decrease within 15minutes of administration while still remaining elevated, relative tooral administration, for up to 120 minutes. In contrast, oraladministration of L-Dopa resulted in a more gradual increase in plasmaL-Dopa levels, which peaked at 15-30 minutes following administrationand then decreased gradually over the next 1-2 hours.

Intravenous, oral and pulmonary delivery also were compared. The resultsare shown in FIG. 14B. This panel depicts the same data presented inFIG. 14A with the addition of the IV administration group which allowsdirect comparisons of the plasma L-Dopa levels obtained following allthree routes of administration (pulmonary, oral, and IV). Data arepresented as the mean i SEM μg L-Dopa/mL blood. Plasma levels of L-Doparapidly increased following intravenous (IV) administration. The highestlevels of L-Dopa were seen at 2 minutes and decreased rapidlythereafter.

Bioavailability was estimated by performing area under the curve (AUC)calculations. Over the entire time course of the study (0-240 min), therelative bioavailability (compared to IV) of pulmonary L-Dopa wasapproximately 75% as compared 33% for oral L-Dopa. The relativebioavailability of pulmonary L-Dopa at 15 min and 60 min postadministration was 38% and 62%, respectively, while that of oral L-Dopawas 9% and 24%, respectively.

Example 7

Pharmacodynamic evaluation of rats receiving L-Dopa also was undertaken.Rats received unilateral injections of the neurotoxin 6-OHDA (specificfor dopamine neurons in the brain) into the medial forebrain bundle.Rats were then screened to assure successful striatal dopamine depletionusing a standard apomorphine-induced turning paradigm. Beginning twoweeks after surgery, animals were tested weekly for three weeks forapomorphine-induced rotation behavior. For this test, animals receivedan IP injection of apomorphine (0.25 mg/kg for the first test and 0.1mg/kg for the following two tests) and were placed into a cylindricalPlexiglass bucket. Each 360-degree rotation was counted for 30 minutesand only those animals exhibiting >200 rotations/30 minutes (12/30lesioned rats) were used in behavioral testing.

The lesioned rats were challenged with several motor tasks post L-Dopaadministration. The data from the studies (placing task, bracing task,akinesia) further emphasized the advantage of pulmonary delivery overoral delivery.

In one test, animals passing the apomorphine challenge were tested usinga “placing task”. Prior to each test day, animals received an IPinjection of the peripheral decarboxylase inhibitor carbidopa (200mg/kg). Animals then received oral L-Dopa (0, 20 or 30 mg/kg) orpulmonary L-Dopa (0, 0.5, 1.0 or 2.0 mg of L-Dopa) and were tested 15,30 60 and 120 minutes later. Throughout testing with oral and pulmonarydelivery of L-Dopa, each animal received every possible drug combinationin a randomized fashion.

The pharmacodynamics “placing task” required the animals to make adirected forelimb movement in response to sensory stimuli. Rats wereheld so that their limbs were hanging unsupported. They were then raisedto the side of a table so that their bodies were parallel to the edge ofthe table. Each rat received 10 consecutive trials with each forelimband the total number of times the rat placed its forelimb on the top ofthe table was recorded.

Results from a “placing task” tests are shown in FIGS. 15A and 15B. Atbaseline (t=0; immediately prior to L-Dopa administration), the animalsperformed nearly perfectly on this task with the unaffected limb, makinggreater than 9/10 correct responses. In contrast, the animals weremarkedly impaired in their ability to perform the same task with theimpaired limb, making approximately 1 correct response over the 10trials.

Oral L-Dopa (FIG. 15A) produced a dose-related improvement inperformance with the impaired limb. At the highest dose tested (30mg/kg), performance was improved, relative to saline control, within 30minutes and peaked between 1-2 hours after drug administration. Thelower dose (20 mg/kg) also improved performance slightly with maximaleffects at 60 minutes and stable performance thereafter. No changes werenoted following administration of the saline control.

In contrast to oral administration, performance on the “placing task”rapidly improved following pulmonary delivery of L-Dopa, as seen in FIG.15B. At the highest dose tested, significant improvements occurredwithin 10 minutes, with peak benefits observed within 15-30 minutes (asopposed to 1-2 hours with oral administration). These effects weredose-related, with significant improvements seen with doses as low as0.5 mg of L-Dopa. In comparison to the recovery shown with oraldelivery, the behavioral improvements were seen with markedly lowertotal doses using the pulmonary route. For instance, the extent ofrecovery with 30 mg/kg of L-Dopa given orally was comparable to therecovery seen with 1 mg of L-Dopa given by the pulmonary route (notethat 1 mg of pulmonary L-Dopa is equivalent to approximately 3 mg/kg,given that the animals body weight was approximately 300 g).Accordingly, when the L-Dopa doses were normalized by body weight, thisrepresented nearly a 10-fold difference in the drug required to produceequivalent efficacy. Finally, the persistence of the behavioralimprovements was comparable using the two delivery routes.

Results from a bracing test are shown in FIGS. 16A and 16B. This testwas performed using the same animals and at the same time as the“placing task” test described above. Rats were placed on a smoothstainless steel surface and gently pushed laterally 90 cm atapproximately 20 cm/second. The number of steps the rat took with theforelimb on the side in which the rat was moving was recorded. Eachtrial included moving the rat 2 times in each direction.

The animals demonstrated a profound impairment in their ability toperform this task with the impaired limb, making approximately 3responses compared to approximately 7 with the unaffected limb, as seenin FIG. 16A. Again, oral administration improved performance on thistask in a dose-related manner. Administration of 30 mg/kg (approximately10 mg L-Dopa) improved performance within 30 minutes. Maximal effectswere seen within 60 minutes and remained stable thereafter. A lower doseof oral L-Dopa (20 mg/kg or approximately 7 mg of L-Dopa) slightlyimproved performance. Again, administration of the saline control didnot affect performance.

In contrast to oral administration, performance on this task rapidlyimproved following pulmonary administration of L-Dopa, as shown in FIG.16B. Significant improvements were seen within 10 minutes, with peakbenefits observed within 15-30 minutes (as opposed to 30-60 minutes withoral administration). These effects were dose-related, with modest, butstatistically significant improvements seen with as low as 0.5 mg(equivalent to approximately 1.5 mg/kg). As with the other functionaltests, the behavioral improvement achieved following pulmonary L-Dopaoccurs at doses far below those required to achieve a similar magnitudeof effect following oral delivery. Finally, the persistence of thebehavioral improvements was comparable using the two delivery routes.

A functional akinesia pharmacodynamics study also was conducted. Theresults are shown in FIGS. 17A and 17B. This test was performed usingthe same animals and at the same time as the two preceding tests. Inthis task, the animal was held so that it was standing on one forelimband allowed to move on its own. The number of steps taken with theforelimb the rat was standing on was recorded during a 30 second trialfor each forelimb.

As was seen with the placing and bracing tests, the animals demonstrateda profound impairment in their ability to perform the akinesia task withthe impaired limb. While the animals made approximately 17 steps withthe normal limb, they made fewer than half this number with the impairedlimb (range=0-10 steps). Oral administration (FIG. 17A) improvedperformance on this task in a dose-related manner. Administration of 30mg/kg (approximately 10 mg L-Dopa) improved performance within 30minutes and maximal effects were seen within 60 minutes. A lower dose oforal L-Dopa (20 mg/kg or approximately 6.8 mg of L-Dopa) produced thesame pattern of recovery although the absolute magnitude of improvementwas slightly lower than that seen with the higher dose of L-Dopa.Performance remained stable between 60 and 120 minutes followingadministration of both doses. Administration of the saline control didnot affect performance.

In contrast to oral administration, performance on this task rapidlyimproved following pulmonary administration of L-Dopa, as depicted inFIG. 17B. Significant improvements were seen within 10 minutes, withpeak benefits observed within 15-30 minutes (as opposed to 60 minuteswith oral administration). These effects were dose-related statisticallysignificant (p<0.05) improvements seen with as low as 1.0 mg. As withthe other functional tests, the behavioral improvement achievedfollowing pulmonary L-Dopa occurred at doses far below those required toachieve a similar magnitude of effect following oral delivery. Finally,the persistence of the behavioral improvements was comparable using thetwo delivery routes.

Animals also were tested on a standard pharmacodynamics rotation testknown to be a sensitive and reliable measure of dopamine activity in thebrain. For this test, animals received either oral L-Dopa (30 mg/kg orapproximately 10 mg total) or pulmonary L-Dopa (2 mg total). These doseswere chosen for this test because they represent the doses of L-Dopashown to produce maximal efficacy in the previous functional tests.Following dosing, animals were placed into a cylindrical Plexiglasbucket. Each 360-degree rotation was counted and grouped into 5 minutebins over a 120 minute test period. Animals were also tested forrotation behavior with and without pre-treatment with carbidopa.

All of the animals used in these studies received unilateral injectionsof 6-OHDA. Because the dopamine depletions are unilateral, theuninjected side remained intact and still able respond to changes indopamine activity. When these animals were injected with a dopamineagonist (i.e. L-Dopa) brain dopamine activity was stimulatedpreferentially on the intact side. This resulted in an asymmetricalstimulation of motor activity that was manifested as a turning orrotational behavior. The onset and number of rotations provided ameasure of both the time course as well as the extent of increaseddopamine activity.

The results are shown in FIG. 18. Oral administration of L-Dopa produceda marked clockwise rotation behavior that was modest during the first10-15 minutes post L-Dopa administration (<5 rotations/animal). Duringthe next 20 minutes, the number of rotations increased markedly, withpeak levels occurring approximately 30 minutes after L-Dopa indicatingincreased dopamine activity in the intact striatum of the brain. Duringthe next 90 minutes, the number of rotations gradually decreased, butthis decrease, relative to peak levels, did not reach statisticalsignificance (p>0.05).

In contrast to oral administration, pulmonary delivery of L-Dopa rapidlyincreased rotation behavior indicating much more rapid conversion ofL-Dopa to dopamine in the intact striatum. Rotations in this group weregreater than 3 times that produced by oral delivery within the first10-15 minutes. The numbers of rotations increased slightly, peaked at25-30 minutes, and remained relatively stable thereafter. While a trendtowards increased rotations, relative to oral delivery, was seen 120minutes after dosing, this did not reach statistical significance(p>0.05). Rotation behavior was virtually eliminated in animals that didnot receive pre-treatment with carbidopa (data not shown).

Example 8

The pharmacodynamic effects of a pulmonary versus oralbenzodiazepine-type drug, alprazolam, were evaluated using a standardpre-clinical test of anxiolytic drug action. In this test, the chemicalconvulsant pentylenetetrazol (PZT), which is known to produce wellcharacterized seizures in rodents, was administered to rats. The testwas selected based on its sensitivity to a wide range of benzodiazapinesand to the fact that the relative potency of benzodiazapines in blockingPZT-induced seizures is believed to be similar to the magnitude of theiranti-anxiety effects in humans. The ability of alprazolam to blockPZT-induced seizures was used as a measure of the pharmacodynamiceffects of alprazolm.

Determinations of the anti-anxiolytic activity of alprazolam were madefollowing oral gavage, or insufflation directly into the lungs of rats.Alprazolam (Sigma, St. Louis, Mo. was administered via aerodynamicallylight particles which included 10% alprazolam, 20% sodium citrate, 10%calcium chloride and 60% DPPC. For oral delivery, alprazolam wassuspended in light corn syrup and administered via gavage. For pulmonarydelivery, an insufflation technique was used. Animals were brieflyanesthetized with isoflurane (1-2%) and a laryngoscope was used tovisualize the epiglottis and the blunt-tip insufflation device(PennCentury Insufflation powder delivery device) was inserted into theairway. A bolus of air (3 cc), from an attached syringe, was used todeliver the pre-loaded powder from the chamber of the device into theanimals' lungs. The doses for pulmonary delivery were 0 (blank particlesthat included 20% sodium citrate, 10% calcium chloride and 70% DPPC),0.088, 0.175, or 0.35 mgs total alprazolam, and the doses for oraldelivery were 0, 0.088, 0.175, 0.35, 0.70, 1.75, or 3.50 mgs totalalprazolam. These doses were chosen to encompass the range of effectiveand ineffective oral doses. Accordingly, any potential benefits ofpulmonary delivery could be directly compared to the oral dose responsecurve for alprazolam.

For both oral and pulmonary delivery, alprazolam was administered either10 or 30 minutes prior to PZT, obtained from Sigma, St. Louis, Mo., (60mg/kg given i.p). To control for potential interactions betweenalprazolam and isoflurane, all animals receiving oral alprazolam alsoreceived isoflurane immediately following dosing as described above. Forall animals, the number of seizures as well as the time to seizure onsetand seizure duration was recorded for 45 minutes after administration ofPZT. Any animal that did not exhibit seizure activity was assigned themaximum possible time for seizure onset (45 minutes) and the minimalpossible time for seizure duration (0 seconds).

Pulmonary delivery of alprazolam produced a rapid and robust decrease inthe incidence of seizures, as shown in Table 11. While 80% of controlanimals (blank particles) exhibited seizures, pulmonary alprazolamproduced a robust and dose-related decrease in the number of animalsmanifesting seizures when administered 10 minutes prior to PZT. Withalprazolam doses as low as 0.088 mgs, only 33% of the animals hadseizures. With further dose escalation to 0.35 mgs of alprazolam,seizure activity was virtually eliminated with only 13% of the animalsexhibiting seizures.

In contrast to the rapid and robust effects of pulmonary alprazolam, theeffects of oral delivery were delayed (Table 11). When given 30 minutesprior to PZT, oral alprazolam produced a dose-related decrease inseizures. While only 27% of the animals had seizures following thehighest dose tested (0.35 mgs), this same dose of alprazolam wasineffective when administered only 10 minutes prior to PZT (i.e, a dosethat was maximally effective when administered by the pulmonary route).These studies also demonstrated that when given 10 minutes prior to PZT,approximately 10 times the oral dose of alprazolam was required toachieve seizure suppression comparable to pulmonary delivery. While only13% of the animals that received 0.35 mgs of particles includingalprazolam had seizures, the oral dose required to produce this effectwas 3.50 mgs.

The benefits of pulmonary delivery over oral delivery were also evidentwhen examining the time to seizure onset (Table 11 and FIG. 19A). Theeffects of oral alprazolam were again delayed relative to pulmonaryadministration. As shown above, oral delivery was markedly lesseffective when alprazolam was given 10 minutes versus 30 minutes beforePZT. In contrast, all doses of pulmonary alprazolam produced rapid androbust effects when given only 10 minutes prior to PZT. Not only werethe effects of pulmonary delivery more rapid, but the effectivepulmonary dose was markedly lower than the effective oral dose. Forinstance, when comparable doses of alprazolam (0.35 mgs) wereadministered by both the oral and pulmonary routes 10 minutes prior toPZT, pulmonary administration resulted in seizure onset times that werenearly maximal (>42 minutes). Oral administration of the same dose ofalprazolam, however, did not increase the latency to seizure onsetrelative to control animals. In fact, oral alprazolam did notsignificantly increase the time to seizure onset until the dose wasescalated to 1.75 mgs and effects comparable to those obtained withpulmonary delivery required an oral dose that was 10 times higher thanthe pulmonary dose (0.35 vs 3.50 mgs).

Similar results were also observed when quantifying the effects of theroute of alprazolam administration on the duration of the seizure (Table11 and FIG. 19B). Pulmonary administration exerted a more rapid effectand also required substantially less total drug relative to oralalprazolam. Again, oral delivery was markedly less effective at reducingthe duration of seizures when alprazolam was given 10 minutes versus 30minutes before PZT. Moreover, the maximally effective oral dose,delivered 10 minutes prior to PZT, was 3.50 mgs of alprazolam. Incontrast, pulmonary delivery of only 0.088 mgs of alprazolam (nearly40-fold lower than the maximally effective oral dose) produced acomparable decrease in seizure duration.

A time course analysis revealed that while the relative advantages ofpulmonary over oral alprazolam declined as the interval betweenalprazolam and PZT was increased, pulmonary delivery remained aseffective as oral delivery. While oral alprazolam became increasinglymore effective as the interval between alprazolam and PZT treatmentincreased from 10 to 30 minutes, the effects of pulmonary deliveryremained relatively constant over the same time period. In fact, nodifferences in seizure activity were seen when comparable oral andpulmonary doses of alprazolam were delivered 30 minutes prior to PZT.While a trend towards fewer seizures was seen with pulmonary delivery,these differences were modest and did not reach statistical significance(Table 11; p>0.05). Moreover, no statistically significant differenceswere observed between any oral and pulmonary dose when comparing thetime to seizure onset or the duration of those seizures (FIGS. 20A).

FIGS. 21A and 21B further demonstrate that the effects of pulmonaryalprazolam remained relatively constant as the time between alprazolamand PZT treatment increased. Importantly though, a detailed analysis ofthe results indicated that alprazolam was modestly more effective whenthe interval between alprazolam and PZT was kept at a minimum. At eachdose tested, fewer animals had seizures when alprazolam was delivered 10minutes vs 30 minutes prior to PZT (although this effect did not reachstatistical significance, p>0.05). The benefit of maintaining a closetemporal relationship between alprazolam and PZT was also beginning toemerge when examining the time to seizure onset and the duration ofseizure activity. While no differences were seen at the higheralprazolam doses (0.175 and 0.35 mgs), animals receiving the lowest doseof alprazolam (0.088 mgs) 10 minutes prior to PZT showed significantlyincreased times for seizure onset and significantly decreased seizuredurations relative to animals treated 30 minutes prior to PZT (FIG. 3).

TABLE 11 Effects of Alprazolam on PZT-Induced Seizures Animals WithMinutes to Seizure Duration of Seizure Route Seizures Onset (seconds)Pulmonary 10 minutes prior to PZT Blank 12/15 (80%) 11.72 (4.63) 83.0(26.04) 0.088 mgs 5/15 (33%) 36.71 (3.93) 7.0 (3.53) 0.175 mgs 3/15(20%) 38.61 (3.81) 8.0 (4.3) 0.35 mgs 2/15 (13%) 42.28 (1.98) 4.0 (2.60)30 minutes prior to PZT Blank 15/15 (100%) 9.58 (2.25) 120.13 (49.33)0.088 mgs 9/15 (60%) 18.47 (5.50) 82.67 (33.0) 0.175 mgs 5/15 (33%)34.05 (4.20) 16.07 (6.89) 0.35 mgs 2/15 (13%) 41.98 (2.18) 2.69 (1.90)Oral 10 minutes prior to PZT 0.35 mgs 13/15 (87%) 11.49 (3.80) 88.0(49.22) 0.70 mgs 13/15 (87%) 9.24 (3.93) 62.07 (14.58) 1.75 mgs 7/15(47%) 29.03 (4.41) 14.47 (4.04) 3.50 mgs 2/14 (14%) 43.37 (1.52) 5.40(3.47) 30 minutes prior to PZT 0 mgs 13/15 (87%) 8.75 (3.95) 96.0(26.08) 0.088 mgs 11/15 (73%) 18.38 (4.55) 46.0 (14.48) 0.175 mgs 7/15(47%) 33.10 (4.07) 15.0 (6.75) 0.35 mgs 4/15 (27%) 37.58 (3.50) 19.0(12.36) Note: all data presented for time to seizure onset and durationof seizure are presented as mean ±SEM

While this invention has been particularly shown and described withreferences to preferred embodiments thereof, it will be understood bythose skilled in the art that various changes in form and details may bemade therein without departing from the scope of the inventionencompassed by the appended claims.

1. A method for treating a disorder of the central nervous systemcomprising administering to the respiratory tract of a patient in needof treatment a drug for treating said disorder, wherein the drug isadministered in a dose that is at least about two times less than thatrequired by oral administration and wherein delivery is to the pulmonarysystem and wherein the drug is present in dry powder particles having atap density of less than 0.4 g/cm³.
 2. The method of claim 1 wherein thedose is between about two times and about five times less than thatrequired by oral administration.
 3. The method of claim 1 wherein thedose is between about two times and about ten times less than thatrequired by oral administration.
 4. The method of claim 1 whereindelivery is to the alveoli region of the pulmonary system.
 5. The methodof claim 1 wherein administering is for rescue therapy.
 6. The method ofclaim 1 wherein administering is during ongoing treatment.
 7. The methodof claim 1 wherein the patient in need of treatment is suffering fromdiseases selected from the group consisting of anxiety, psychosis,depression, bipolar disorder, obsessive compulsive disorder,convulsions, seizures, epilepsy, Alzheimer's, attention deficithyperactivity disorder and migraines.
 8. The method of claim 1 whereinthe drug is present in the dry powder particles in an amount of at least20 weight percent.
 9. The method of claim 1 wherein the drug is presentin the dry powder particles in an amount of at least 40 weight percent.10. The method of claim 1 wherein the drug is present in the dry powderparticles in an amount of at least 50 weight percent.
 11. The method ofclaim 1 wherein the particles have a mass median aerodynamic diameter ofless than about 5 microns.
 12. The method of claim 1 wherein theparticles have a mass median geometric diameter greater than about 5microns.
 13. The method of claim 1 wherein the particles have a massmedian aerodynamic diameter of less than about 3 microns.
 14. The methodof claim 1 wherein the particles include a phospholipid.
 15. The methodof claim 1 wherein the particles include an amino acid.
 16. The methodof claim 15 wherein the amino acid is leucine.
 17. The method of claim 1wherein the particles are administered via a dry powder inhaler.
 18. Amethod for treating a disorder of the central nervous system comprisingadministering to the respiratory tract of a patient in need of treatmenta drug for treating said disorder, wherein the drug is administered in adose that is at least about two times less than that required byadministration routes other than intravenous and wherein delivery is tothe pulmonary system and wherein the drug is present in dry powderparticles having a tap density of less than 0.4 g/cm³.
 19. A method fordelivering ketoprofen to the central nervous system comprisingadministering to the respiratory tract of a patient in need of treatmentor rescue therapy with ketoprofen, wherein ketoprofen is administered ina dose that is at least about two times less than that required by oraladministration and wherein delivery is to the pulmonary system andwherein the drug is present in dry powder particles having a tap densityof less than 0.4 g/cm³.
 20. A method for delivering a benzodiazepinedrug to the central nervous system comprising administering to therespiratory tract of a patient in need of rescue therapy with abenzodiazepine drug, wherein the benzodiazepine drug is administered ina dose that is at least about two times less than that required by oraladministration and wherein delivery is to the pulmonary system andwherein the drug is present in dry powder particles having a tap densityof less than 0.4 g/cm³.
 21. A method of providing rescue therapy to thecentral nervous system comprising: administering to the respiratorytract of a patient in need of rescue therapy particles comprising aneffective amount of a benzodiazepine drug wherein the drug is present indry powder particles having a tap density of less than 0.4 g/cm³. 22.The method of claim 21 wherein the rescue therapy is for a panic attack.23. The method of claim 21 wherein the benzodiazepine drug is present inthe particles in an amount ranging from about 1 to about 90 weightpercent.
 24. The method of claim 21 wherein the particles have a volumemedian geometric diameter of between about 5 micrometers and about 30micrometers.
 25. The method of claim 21 wherein the particles have anaerodynamic diameter of between about 1 and about 5 microns.
 26. Themethod of claim 25 wherein the particles have an aerodynamic diameter ofbetween about 1 and about 3 microns.
 27. The method of claim 25 whereinthe particles have an aerodynamic diameter of between about 3 and about5 microns.
 28. The method of claim 21 wherein delivery to the pulmonarysystem includes delivery to the alveoli.
 29. The method of claim 21wherein the particles include a phospholipid.
 30. The method of claim 29wherein the phospholipid has a matrix transition temperature which is nohigher than the patient's physiological temperature.
 31. The method ofclaim 29 wherein the phospholipid is present in the particles in anamount ranging from about 10 to about 99 weight percent.
 32. The methodof claim 21 wherein the particles include a hydrophobic amino acid. 33.The method of claim 32 wherein the hydrophobic amino acid is present inthe particles in an amount of a least 10% by weight.
 34. The method ofclaim 21 wherein the particles further include calcium chloride.
 35. Themethod of claim 21 wherein delivery to the pulmonary system is by meansof a dry powder inhaler.
 36. The method of claim 21 wherein delivery tothe pulmonary system is by means of a metered dose inhaler.